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Cooperation between the IAEA and international financial institutions in the nuclear field: from diplomacy to practical action

The IAEA, together with the World Bank Group, other international financial institutions and multilateral development banks, has entered a new stage of cooperation.

February 15, 2026

Jeffrey Donovan, IAEA Department of Nuclear Energy

IAEA Director General Rafael Mariano Grossi met with representatives of the World Bank Group, the Asian Development Bank, the EBRD, the OPEC Fund, and other banks during their official visit to IAEA Headquarters in Vienna, Austria, 15 January 2026. Photo: D. Calma/IAEA

The IAEA, together with the World Bank Group, other international financial institutions (IFIs) and multilateral development banks (MDBs), has entered a new phase of engagement, moving from diplomatic agreements to practical project implementation as the Agency expands its support for their efforts to use nuclear energy for development.

Following the signing of a landmark partnership agreement on nuclear energy cooperation between the IAEA and the World Bank Group (WBG) last June, a workshop was held earlier this month at the IAEA Headquarters in Vienna to discuss next steps, including expanding cooperation with other international financial institutions and multilateral development banks, clarifying roles, aligning technical and regulatory requirements, and implementing concrete measures to assist countries in developing nuclear energy, taking into account IAEA nuclear safety, security, and non-proliferation standards.

Expanding cooperation

The seminar brought together leading experts from not only the World Bank Group but also other major financial institutions, including the European Bank for Reconstruction and Development (EBRD), the Asian Development Bank (ADB), and the OPEC Fund for International Development. Participants discussed issues such as radioactive waste management, emergency preparedness and response, and the development of the institutional framework necessary for investors to support large-scale nuclear infrastructure projects.

"Building on the agreements recently reached with international financial institutions, we view their practical implementation as a priority," said IAEA Director General Rafael Mariano Grossi. "It is crucial for us that leading experts from these organizations have gathered here at the IAEA today to outline ways to expand our cooperation and support countries in various areas of nuclear energy and non-energy technology applications—from health and food security to water resource management and environmental protection."

Last June, in Paris, Director-General Grossi and World Bank Group President Ajay Banga signed a memorandum of understanding to deepen cooperation in three areas: building a nuclear energy knowledge base within the WBG, supporting the long-term operation of existing nuclear power plants, and advancing small modular reactor (SMR) technology. This agreement marked the Group's first formal resumption of nuclear energy activities in decades and served as a signal for other international financial institutions to follow suit.

Additional agreements

Since then, the IAEA has entered into cooperation agreements with other MDBs, including the Asian Development Bank and the OPEC Fund, demonstrating a more coordinated approach among international organizations to assessing the potential role of nuclear energy in generating clean and reliable electricity. This is particularly relevant for countries seeking sustainable economic growth while reducing greenhouse gas emissions.

"The World Bank Group is rethinking its approach and renewing its engagement in nuclear energy, thereby expanding countries' ability to meet their energy needs," said Lauren Culver, Senior Energy Specialist at the WBG. "This workshop provided an important opportunity to deepen our collaboration with the IAEA and strengthen our capacity to finance nuclear projects that comply with IAEA standards on nuclear safety, security, regulatory frameworks, and non-proliferation safeguards."

The seminar focused on legal aspects, namely how funding to support institutional and policy reforms can facilitate the adoption of international treaties and the incorporation of nuclear safety, security and safeguards obligations into national legislation.

Other sessions examined the role of development banks in financing technical work during the preparatory phase, which often precedes major investment decisions. These activities include developing feasibility studies for SMRs, planning for radioactive waste disposal, and developing infrastructure during the initial stages. Issues related to the front-end of the fuel cycle were also discussed, including conducting comprehensive assessment missions for the uranium production cycle, as well as the role of research reactors as a key element in building nuclear capability.

Environmental and social standards

During the discussions, special attention was also paid to compliance with environmental and social standards. "Environmental and social standards are not a formality, but the foundation of responsible investment. We were particularly pleased to collaborate with the IAEA and other financial institutions that are committed to their proper application, particularly in the area of nuclear energy safety," emphasized Gerardo Parco, Acting Director for Sustainable Development and Climate Change at the OPEC Fund for International Development.

“This workshop demonstrated how the EBRD can leverage the IAEA’s expertise and experience to support countries in developing nuclear energy in a safe and sustainable manner, while ensuring investor confidence,” said Debbie Cousins, Director of Operations in the Environment and Sustainability Department at the European Bank for Reconstruction and Development. “Building on the IAEA’s more than 30 years of experience in 170 member states, we can develop a robust approach to ESG risk management that benefits operators and regulators, host countries, and investors alike. The EBRD looks forward to further strengthening this partnership as a model for responsible support of nuclear energy by multilateral development banks.”

The seminar marked a transition to a more coordinated collaboration. During the discussions, interest was also expressed in holding similar events at the regional level, as developing countries are seeing growing demand for nuclear technology.

"The seminar provided a unique opportunity to gain a detailed understanding of nuclear safety, waste management, emergency response, and related areas," noted Ki Young Nam, Lead Energy Economist at the Asian Development Bank. "Given its relevance and practical significance, holding a similar seminar for the Asian Development Bank would be highly beneficial for further strengthening nuclear energy programs in the Asia-Pacific region."

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A course of radiation therapy consists of several sessions, during which the patient's body must be kept in the same position.

For most types of radiation therapy to the brain, head, or neck, patients wear a special thermoplastic mask that immobilizes their head to maintain a specific body position during the procedure. This allows for precise radiation delivery to the tumor, minimizing exposure to healthy tissue.

Some hospitals paint children's masks brightly colored or styled like favorite characters. Pretending to be superheroes helps children feel more confident during the procedure and cope better with the treatment.

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The Ukrainian electrical grid was again the target of military activity, over the past weekend, leading to significant impacts to several regions of Ukraine and nuclear power plant (NPP) operations, stated by International Atomic Energy Agency (IAEA) Director General Rafael Mariano Grossi.

Power lines linking Ukraine with neighboring countries were disconnected, triggering a cascade of power lines being disconnected within Ukraine. As a result, a unit at one NPP disconnected from the grid due to fluctuations and automatically shutdown. Other units at other NPPs were forced to reduce power. The Chornobyl site experienced a complete loss of off‑site power and relied on its emergency diesel generators for approximately one hour.

"This latest grid event in Ukraine is a stark reminder of the ever-present risks to nuclear safety and security arising from deteriorating grid conditions. Extensive repairs are needed to improve the reliability of power supply to Ukrainian NPPs and to strengthen their resilience to further grid events," Director General Grossi said. “Once again, I call for maximum military restraint, as well as full observation of the Seven Indispensable Pillars to enable these essential repairs to take place.”

Amid increased military activity impacting the Ukrainian electrical grid, three IAEA teams are visiting 10 substances critical to nuclear safety and security in Ukraine. The objective of this two-week IAEA mission is to assess the continuing damage to the grid, review repair efforts and identify practical steps to strengthen the resilience of off-site power supplies to the country's NPPs. One of the teams has also visited Kyiv, where they discussed further IAEA support to NPP operations under deteriorating grid conditions.

This is the second such mission in as many months; the previous mission took place inDecember 2025, which confirmed the effects of cumulative impacts on NPP operations and staff conditions.

Further evidence of decreasing grid stability within Ukraine was apparent at the Chornobyl NPP in late-January. The IAEA team was informed that the diesel generators for the site's New Safe Confinement and the Interim Spent Nuclear Fuel Dry Storage Facility unexpectedly started on Friday, 23 January, due to fluctuations from the grid. The diesel generators for both facilities were manually put in standby mode within minutes. “This further highlights the impact that military activity on the grid can have on safety systems,” Director General Grossi added.

Earlier last week, Chornobyl NPP detected 44 drones within their surveillance zone. On Tuesday last week, the IAEA team at Rivne NPP sheltered at their hotel, while two drones were detected within the plant's surveillance zone. Another six drones were detected at Rivne NPP last week.

Over the past two weeks, IAEA teams at the Khmelnitsky and South Ukraine NPPs safely rotated.

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Technicians have successfully completed crucial power line repairs near Ukraine's Zaporizhzhya Nuclear Power Plant (ZNPP), carried out with security assurances provided by both sides under an IAEA-brokered local ceasefire, Director General Rafael Mariano Grossi said today.

It was the third time in recent months that temporary truce arrangements negotiated and supervised by the IAEA enabled the reconnection of power lines vital for nuclear safety that had been damaged during the military conflict. In late October, such a “window of silence” made it possible to end the ZNPP's tenth and longest complete loss of off-site power event so far during the conflict.

This time, it allowed the restoration of power transmission between the electrical switchyards of the ZNPP and the nearby Zaporizhzhya Thermal Power Plant two weeks after it was cut, reportedly due to military activity. The connection is important as it offers a key route for electricity supplied by one of the ZNPP's two available power lines, a 330 kilovolt (kV) line.

Monitored by the IAEA team based at the ZNPP, the repairs that began on Sunday morning were completed on Monday afternoon, after both the damaged transmission line and a separate issue with the ZNPP switchyard's autotransformer had been fully addressed and restored.

“The successful repairs carried out this week – as well as those in October and November – demonstrate that it is possible for an organization like the IAEA to work with both sides of the conflict in order to achieve a common objective: preventing a nuclear accident that would be in no one's interest,” Director General Grossi said.

"I would like to thank both the Russian Federation and Ukraine for engaging constructively with us in making this possible by agreeing to another localized ceasefire. As a result, we have managed to take a crucial step in supporting nuclear safety and security. However, the overall situation at the Zaporizhzhya Nuclear Power Plant and Ukraine's other nuclear sites remains precarious and our work is far from finished," he said.

Nuclear power plants need off-site power to cool their reactor and spent fuel and for other essential safety and security functions, even when they are not producing electricity, as is the case with the ZNPP. The plant, Europe's largest, had 10 power lines available before the conflict, compared with the two that remain now.

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Sustainability and Innovation in Cancer Care

Located in four regions around the world, the Rays of Hope Initiative support centres support IAEA technical cooperation activities by training personnel in oncology and medical physics, and by promoting research to ensure the most efficient use of limited resources.

To strengthen clinical practice and support the implementation of programs under the Rays of Hope initiative, a number of new coordinated research projects (CRPs) in cancer treatment will be implemented in collaboration with reference centers. A key step in the radiation therapy planning process was the recently launched CRP on prostate cancer delineation using computed tomography (CT) and AI-based verification, in which all 18 reference centers were invited to participate.

The reference centres also provide data to the Sustainable Unified Network for Innovation and Scientific Efficiency in Radiation Medicine (SUNRISE), a global database designed to collect reliable and timely data from cancer centres to measure and demonstrate the impact of improvements in radiation medicine practice, with a focus on sustainability and cost-effectiveness.

More than 500 specialists took part in the in-person workshops organized at these centers, and another 200 specialists participated remotely.

Oncologists in Asia have learned about cutting-edge treatments, including ultra-hypofractionated radiation therapy, which reduces treatment time and costs, and theranostics, a combined method of diagnosing and treating tumors using radiopharmaceuticals.

In Europe, Central Asia and Latin America, radiation medicine experts shared information on best practices in pediatric oncology to improve cancer care for children.

To ensure long-term sustainability, the IAEA continues to provide targeted training at the support centres, providing the network with the necessary knowledge and assistance for transfer to neighbouring countries.

"Soon after joining the Rays of Hope initiative as a reference center, we participated in an IAEA workshop to develop a standardized curriculum for gynecologic oncology and received virtual reality tools from the Agency for practicing brachytherapy procedures. Thanks to this support, we were able to adopt a more structured and standardized approach to training, which we now teach to specialists from across the region at our reference center," notes Dr. Umesh Mahantshetti, a radiation oncologist at the Tata Centre.

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Medical imaging plays a crucial role in cancer care, enabling radiation therapy planning, treatment delivery, and evaluation of its effectiveness. The use of advanced imaging techniques in radiation therapy has revolutionized cancer treatment and improved patient outcomes. In this context, medical imaging serves the following functions.

Assessment of localization and spread of the disease

Medical imaging can determine whether cancer is in its early stages or has spread to other parts of the body. Imaging-guided procedures, such as biopsies, are minimally invasive and essential for accurate tissue diagnosis.

Medical imaging techniques such as computed tomography (CT), ultrasound, magnetic resonance imaging (MRI), and positron emission tomography (PET) are essential for accurate diagnosis and cancer staging. These techniques help determine the location, size, and extent of tumor spread, as well as its relationship to adjacent tissues and the presence of metastases.

Creating a treatment plan

Imaging is used in treatment planning, ranging from medication and radiation therapy to surgery or, in some cases, palliative care. When planning radiation therapy, imaging creates 3D images of the tumor, allowing for more precise targeting of radiation while minimizing damage to healthy tissue.

Image-guided radiation therapy (IGRT) utilizes real-time medical imaging during radiation therapy. This method ensures precise and uniform delivery of radiation doses.

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2. There are 416 power units in operation worldwide.

PRIS continuously collects various data on power units, and this information is updated regularly. As of November 19, 2025, the total capacity of all 416 operating power units worldwide was 376.3 GW(e). In 2024, there were 421 operating power units, with a total generating capacity of 377.0 GW(e), generating approximately 2,617.3 TWh of electricity—enough to provide low-carbon energy for hundreds of millions of homes.

The United States remains the world's largest producer of nuclear energy, with 94 nuclear power units (96,952 MW(e)) in operation. In 2024, they generated approximately 781.9 TWh of electricity.

China is rapidly expanding its nuclear power plant fleet, with 57 units (55.3 GW(e)) in operation and another 29 (29.6 GW(e)) under construction. In 2024, Chinese nuclear power plants generated over 417.5 TWh of electricity.

Nuclear energy also plays a significant role in the electricity generation mix of European countries. France leads the way with 57 nuclear power units (63.0 GW(e)), which generated approximately 67.3% of the country's total electricity in 2024—the highest share in the world.

Other European countries with a high share of nuclear electricity generation include Slovakia (60.6%), Hungary (47.1%) and Finland (39.1%).

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Ukraine's Zaporizhzhya Nuclear Power Plant (ZNPP) was reconnected to its last remaining backup power line on Monday after successful repairs were completed under a temporary ceasefire negotiated by the International Atomic Energy Agency (IAEA), Director General Rafael Mariano Grossi said today.

The backup 330-kilovolt (kV) line was damaged and has been disconnected since January 2, reportedly because of military activity. Since then, ZNPP has relied on its last remaining 750-kV main power line to provide the off-site power needed to operate safety systems to cool the ZNPP's six shutdown reactors and spent fuel pools.

After the repair site was cleared of any unexploded ordinance on Saturday, a specially deployed IAEA team monitored the repairs conducted on the frontline by Ukrainian technicians on Sunday and Monday.

"The IAEA continues to play a vital role to maintain nuclear safety and security at the ZNPP. This was the fourth temporary ceasefire agreement that we have negotiated between both sides, for five separate repairs of power lines connected to the ZNPP," Director General Grossi said. “Now that the site has regained connection to both off-site power lines, I once again call on both sides to abide by the Five Concrete Principles to avoid a nuclear accident at the ZNPP by making all efforts to avoid any future damage to these lines.”

The team continues to monitor nuclear safety and security at the site, especially in consideration of winter conditions. Under normal operations, residual heat from the operating reactor units keeps the water temperature in the cooling pond and sprinkler ponds warm. With the reactors shut down, less heat is generated, potentially increasing the risk of the water freezing.

During a walkdown on Sunday, the IAEA team observed large ice formations on fountain pipes in some sprinkler ponds. A follow‑up walkdown today confirmed that the ice formations were no longer present. The team also confirmed that all 11 groundwater wells remain operational and continue supplying water to the sprinkler ponds, despite the sub-zero conditions. The IAEA team will continue to monitor this issue.

The IAEA team also conducted walkdowns of the Unit 4 reactor building and its safety system rooms, the turbine halls of Units 3 and 4—where the team could not gain access to the western part of the building—and the Unit 6 electrical, instrumentation and control rooms. They also observed routine testing of an emergency diesel generator (EDG) of Unit 3.

Elsewhere in Ukraine, IAEA teams reported military activities in proximity of nuclear power plants (NPPs). Last Friday, one drone was reported approximately 10 kilometers (km) from the South Ukraine NPP. On Tuesday morning, three drones were reported about 5 km from the Chornobyl NPP site, and military activities on Tuesday damaged a critical substation, resulting in the disconnection of power lines to the Chornobyl NPP site and one of the operating NPPs.

At the Chornobyl NPP, one 750-kV power line and two 330-kV lines were lost on Tuesday morning. Though the site received power from other off‑site power lines, the EDGs for the New Safe Confinement operated three times during the day, and the EDGs for the Interim Spent Fuel Storage Facility‑2 operated once during the day either as a result of the line disconnection or due to power fluctuations. A 110-kV line was also disconnected on Tuesday and again on Wednesday.

An IAEA mission will deploy on Monday to assess the condition of Ukraine's critical substances and their implications for nuclear safety at Ukraine's nuclear facilities. “These critical substances are essential for ensuring reliable off‑site power, a key requirement under Pillar 4 of the Seven Indispensable Pillars of nuclear safety,” Director General Grossi said. “Any damage to this infrastructure undermine nuclear safety and must be avoided.”

This week, IAEA teams at the Chornobyl NPP site and the Rivne NPP safely rotated.

The Agency continued with deliveries under the comprehensive program of assistance to help Ukraine maintain nuclear safety and security amid the on-going conflict. This week, five electric all-terrain vehicles were delivered to the State Specialized Enterprise “Association Radon” to support the needs of its physical protection department. Within the scope of the medical program, the medical unit of the Chornobyl NPP received medications for the needs of their staff.

The deliveries, which brought the total number of shipments to Ukraine to 198 and totaling €21.9 million worth of equipment since the start of the conflict, were made possible with funds from the United Kingdom and the European Union.

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What is an atom?

What's what in the nuclear sphere?

Atoms are the fundamental building blocks of matter. Everything that surrounds us—air, water, rocks, plants, and animals—as well as ourselves and our bodies, is made up of atoms.

January 21, 2026

Emma Midgley, Public Information and Communications Bureau

An atom is the smallest particle of a chemical element, containing all of its chemical properties. It consists of protons, neutrons, and electrons.

Atoms are extremely tiny; they are the smallest particles of a chemical element that retain all of its chemical properties. The ancient Greeks believed them to be the smallest particles in existence—the word "atom" itself means "indivisible" in Greek. The thickness of a human hair contains approximately 500,000 carbon atoms.

A single strontium atom becomes visible because it absorbs laser light and then re-emits it. The distance between the electrodes in the photograph is 2 millimeters. Photo: David Nadlinger / University of Oxford

Atoms cannot be seen with the naked eye or even with a standard optical microscope, as they are too small to deflect visible light waves. However, atoms can be viewed with an electron microscope, which generates electron waves capable of interacting with atoms. In the photograph above, the atom became "visible" because it absorbed and then re-emitted laser light.

What do atoms look like? Scientists have changed their minds over the centuries.

What are atoms made of?

Every atom consists of three types of particles: protons, neutrons, and electrons. At the center of the atom is a dense nucleus containing protons and neutrons, yet it is significantly smaller than the atom as a whole. If the nucleus of an atom were the size of a dice, the atom itself would be the size of a sports stadium.

Protons have a positive electrical charge, while neutrons are electrically neutral. The nucleus does not decay due to nuclear forces of attraction. These forces bind protons and neutrons at distances close to the size of the nucleus. At such distances, the nuclear force is significantly stronger than the electrical repulsion between protons (otherwise, due to their equal charges, they would repel each other). At greater distances, the nuclear force quickly weakens to negligible strength.

The number of protons in an atom's nucleus determines what element it is. For example, an atom with one proton is hydrogen, while an atom with eight protons is oxygen.

The nucleus of an atom is surrounded by a cloud of electrons—negatively charged particles. The nucleus and electrons are bound together by the Coulomb force—a force in physics that determines the repulsion or attraction between similarly charged particles. However, if an electron receives sufficient energy, it can separate from the atom, turning the atom into a positively charged ion.

The atom in the center of the IAEA logo contains four electrons—it is a neutral, non-ionic beryllium atom.

What are ions?

Atoms with an equal number of negatively charged electrons and positively charged protons are neutral because their charges cancel each other out. If an atom gains or loses electrons, it becomes an ion.

The electric field of a neutral atom is weak, while an electrically charged or ionized atom has a strong electric field—because of this, it is strongly attracted to oppositely charged ions and molecules. Atoms can become ionized through collisions with other atoms, ions, and subatomic particles. They can also be ionized by exposure to gamma or X-ray radiation. Ionizing radiation is radiation with sufficient energy to separate an electron from an atom. Furthermore, exposure to such radiation can alter the chemical composition of a substance, which can lead, for example, to DNA damage in living tissue.

Most atoms on Earth are stable primarily because of the balanced composition of particles (neutrons and protons) in their nuclei.

However, in some types of unstable atoms, the number of protons and neutrons in their nuclei prevents them from holding together. This "decay" of the atom releases energy in the form of radiation (e.g., alpha particles, beta particles, gamma rays, or neutrons), which—under controlled conditions and with appropriate safety precautions—can be used for a variety of purposes.

Ernest Rutherford: Inventor of the First Nuclear Fission Device

In 1917, scientist Ernest Rutherford discovered that when beams of radioactive alpha particles collide with nitrogen gas, the nitrogen atom splits into oxygen and a hydrogen nucleus. This subatomic particle (the hydrogen nucleus) was later renamed the proton.

Rutherford's discovery led to the creation of the first particle accelerator, initially called an "atom smasher." This powerful device could use an electric field to accelerate charged particles to high energies along a specific trajectory and, using strong magnets, to create beams of single charged particles. When these fast-moving particles, whose speeds can approach the speed of light, hit a target, the atoms in the target were disintegrated.

Additionally, particle accelerators can be used to create radioactive material – atoms are bombarded with charged particles to turn them into other, unstable atoms, such as technetium-99m, used for medical imaging, or radioisotopes for targeted cancer therapy.

Today, particle accelerators are also used to sterilize medical equipment, study the origins of the universe (for example, at the Large Hadron Collider), analyze air samples, and refine materials and increase their resistance to damage. There are many types of particle accelerators, including ion implanters, electron beam accelerators, cyclotrons, synchrotrons, linear accelerators (linacs), and electrostatic accelerators.

Splitting an atom: nuclear fission reaction

In the 1930s, scientists discovered that when certain uranium atoms are bombarded with neutrons—uncharged subatomic particles—they can split into two fragments and emit a number of neutrons, releasing a huge amount of energy. This process is called fission.

Of all the naturally occurring elements on Earth, uranium has the highest atomic number, with a nucleus containing 92 protons. Uranium-235 fissiles more easily than other isotopes because its nucleus is relatively unstable and readily absorbs neutrons, causing it to split into two lighter atoms. However, only 0.7% of the uranium in the Earth's crust is of this fissile type.

The fission process can initiate a nuclear chain reaction. Each splitting of a uranium-235 atom releases an average of 2.5 neutrons. These neutrons, in turn, can split other fissile uranium nuclei, releasing even more neutrons. However, these "fast" neutrons initially propagate with too much energy, making them ineffective in initiating fission. The use of "moderators," such as water or graphite, can reduce the speed of neutrons. Upon collision with hydrogen or carbon atoms, neutrons lose most of their energy, becoming "thermal" or "slow" neutrons, which are much more likely to split other uranium nuclei.

Nuclear fission technology currently accounts for 10% of the world's carbon-free energy generation because the reaction does not produce carbon dioxide.

What happens to atoms during nuclear fusion?

Nuclear fusion is a process in which two light atomic nuclei combine to form a single heavier nucleus, releasing a massive amount of energy. This theory was first formulated in the 1920s.

Thermonuclear reactions occur in matter in a plasma state—a hot, charged gas composed of positive ions and freely moving electrons that has unique properties distinct from those of solids, liquids, or gases.

It is this reaction that provides the energy for the Sun and all other stars. To achieve fusion on the Sun, nuclei must collide at extremely high temperatures—around one hundred million degrees Celsius. This high temperature provides them with enough energy to overcome their mutual electrical repulsion. Once the nuclei overcome this repulsion and are very close to each other, the nuclear forces of attraction between them become stronger than the electrical repulsion, allowing them to fuse.

For this to occur, the nuclei must be confined to a confined space, which increases the likelihood of their collision. On the Sun, the conditions for thermonuclear fusion are created by the colossal pressure generated by its powerful gravity.

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The IAEA today secured the agreement of both the Russian Federation and Ukraine to implement a localized ceasefire enabling repairs to begin on the last remaining backup power line to Ukraine's Zaporizhzhya Nuclear Power Plant (ZNPP), IAEA Director General Rafeal Mariano Grossi confirmed.

Technicians from Ukraine's electrical grid operator are expected to begin repair work on the 330 kV line – damaged and disconnected as a result of military activity on January 2 – in the coming days. The disconnection has left Europe's largest NPP dependent on its sole functioning 750 kV main power line.

An IAEA team has departed Vienna to travel to the frontline in order to observe the repair works.

"The IAEA continues to work closely with both sides to ensure nuclear safety at the ZNPP and to prevent a nuclear accident during the conflict. This temporary ceasefire, the fourth we have negotiated, demonstrates the indispensable role that we continue to play," IAEA Director General Rafael Mariano Grossi said today.

The IAEA team based at the ZNPP this week appreciated the actions taken by the plant to ensure nuclear safety during adverse weather conditions. During walkdowns, the team confirmed that winter protection measures are in place to prevent freezing of water in the groundwater wells, which supply cooling water for safety systems that cool the reactors and spent fuel pools. The ZNPP informed the team that the pumps operating in the unit pumping stations of the six shutdown reactors, would continue to work even if ice was to form on the surface of the inlet channel, and that currently no ice had been observed in that area.

Additional efforts against the freezing temperatures include temperature controls for local heating to ensure that the emergency diesel generators are ready to start and operate properly in case of another loss of off-site power event. The team continues to monitor the measures taken.

At Ukraine's Chornobyl Nuclear Power Plant (NPP) site, one power line was disconnected in the past week after military activity damaged an electrical substation critical to its power supply, a development that once again underscores the importance of reliable electrical grid infrastructure for nuclear safety, IAEA Director General Rafael Mariano Grossi said today.

Following damage to the substation, the Chornobyl NPP site continued to receive off-site power from other lines, with the disruption illustrating the essential role substations play in ensuring the continuous supply of electricity required to operate key safety systems.

The disconnection was one of several incidents this week in which military activity affected nuclear safety at Ukraine's nuclear facilities. Last weekend, one of Ukraine's three operating NPPs was also forced to temporarily reduce its power output after reported damage to the electrical infrastructure.

“A deterioration of Ukraine's power grid from persistent military activity has direct implications on the nuclear safety of its nuclear facilities,” said Director General Grossi. “The IAEA will, as a priority, continue to assess the functionality of these critical substances.”

Director General Grossi announced last week that the IAEA is preparing another expert mission to Ukraine's electrical substations amid ongoing strikes on the country's power infrastructure. These substances are essential for supplying electricity needed for reactor cooling systems and other key nuclear safety functions. The mission will assess 10 substances critical to nuclear safety, following up on some of those visited in December 2025 and examining additional sites not previously assessed.

IAEA teams reported military activities or air raid alarms at all five nuclear sites in Ukraine over the past week. The teams at the Chornobyl site and at the Khmelnitsky NPP were informed that military objects flying within five kilometers of the sites had been observed on 11 and 15 January, respectively. At ZNPP, the team continues to hear a large number of explosions, including some within the vicinity of the site. The team at the South Ukraine NPP has reported multiple air raid alarms each day over the past week and were informed that a military flying object had been observed approximately 10km from the site.

Please note: This information is raw content obtained directly from the source. It represents an accurate account of the source's assertions and does not necessarily reflect the position of MIL-OSI or its clients.