UN Secretary-General António Guterres on July 5 strongly condemned Russia's largest yet wave of drone and missile attacks in Ukraine, especially noting strikes that disrupted the power supply to the Zaporizhzhia Nuclear Power Plant (ZNPP), endangering nuclear safety. A statement issued by Guterres' office said:

The Secretary-General is alarmed by this dangerous escalation and the growing number of civilian casualties. Attacks against civilians and civilian infrastructure are prohibited under international law and must stop immediately

Rafael Mariano Grossi, director general of the International Atomic Energy Agency (IAEA), also warned of the persisting "extremely fragile" situation at the Europe's largest nuclear facility.

Russia's latest air-strike against the ZNPP on July 4 disrupted the plant's last external power connection, forcing it to rely on emergency diesel generators for more than three hours. This was the ninth time power was cut off to the plant since the war began in February 2022. Although external power has been restored, Grossi cautioned that the situation remains unsafe.

Article 56 of Additional Protocol I to the Geneva Conventions, to which Russia is a party, prohibits targeting nuclear power plants as military objects unless the plant supplies electric power "in regular, significant and direct support of military operations," and the attack is the only available means to halt such support. Recent resolutions passed by the IAEA General Conference and the UN General Assembly have reiterated Russia's obligations to refrain from attacking nuclear plants.

The Zaporizhzhia Nuclear Power Plant, the largest nuclear power facility in Europe, has become extremely vulnerable since being militarily seized by Russia in 2022. Although its six reactors have been in cold shutdown since 2024, it still relies on one remaining external power line for electricity supply to cool reactor cores. The other nine power lines have been disconnected due to military activities. The cooling process is essential to prevent overheating and potential radioactive release.

Although there are concerns over potential catastrophic nuclear disaster resulting from the attacks, Antony Froggatt, the former deputy director of the Environment & Society Centre at the British  think-tank Chatham House, and Dr. Patricia Lewis, the former research director at the International Security Programme, Chatham House, claimed that "the impact would likely be nowhere near as severe as the 1986 Chernobyl disaster and more likely be similar in scale to the 2011 Fukushima nuclear crisis," due to the type of reactors used at the ZNPP. Notably, the current Water-Water Energetic Reactors (VVER) utilized at the ZNPP are not moderated by graphite, but by water.

From JURIST, July 6. Used with permission.

Note: Fukushima still remains the world second worst nuclear disaster after Chernobyl.

See our last report on the Zaporizhzhia nuclear plant.