The UN issued a stark warning on Friday after Russian forces attacked Europe's largest nuclear facility, and seized it from Ukrainian authorities.
The attack on Ukraine's Zaporizhzhia Nuclear Power Plant resulted in a fire erupting at a training complex at the site, which was extinguished by Ukrainian firefighters. UN officials reported that no radiation was released, and that essential equipment was not affected.
"Attacks on nuclear power facilities are contrary to international humanitarian law,” Rosemary DiCarlo, the UN's Deputy Under-Secretary for Political and Peacebuilding Affairs, told the Security Council during an emergency session called by the UK to address the early morning attack.
DiCarlo said it is "vital" that Russia and Ukraine develop "an appropriate framework" to work with the UN's nuclear watchdog, the International Atomic Energy Agency (IAEA), to "ensure the safe, secure and reliable operation of Ukraine’s nuclear power plants."
"Urgent and safe passage should be granted to IAEA personnel should they need to travel to Ukraine to work with regulators," she said.
Located in southeastern Ukraine near the city of Enerhodar, the Zaporizhzhia plant generates 20% of Ukraine's electricity. A total of six reactors, each with a net capacity of 950 megawatts, can supply energy to nearly 4 million households with a total electricity production of 5,700 megawatts.
Linda Thomas-Greenfield, the US's UN envoy, sharply denounced Russia's attack, saying it risked a catastrophe that would have been felt far beyond Ukraine's borders.
"By the grace of God the world narrowly averted a nuclear catastrophe last night. We all waited to exhale as we watched the horrific situation unfold in real-time," she said. "It was incredibly reckless and dangerous and it threatened the safety of civilians across Russia, Ukraine and Europe. As a first step, we call on Russia to withdraw its troops from the plant."
'It must not happen again'
The UK's ambassador said the attack marks the "first time that a state has attacked a fueled and functioning nuclear power plant."
"International law requires special protection for nuclear facilities, and it is difficult to see how Russia’s actions were compatible with its commitments," Dame Barbara Woodward said. "It must not happen again.”
Russia, however, denied attacking the facility, and dismissed Friday's emergency convening of the Security Council as an effort "to kindle artificial hysteria about what is taking place in Ukraine."
Vassily Nebenziya, Moscow's UN ambassador, claimed Russian troops came under attack from "saboteurs" operating at the nuclear site's training facility, and returned fire. He said it was Ukrainians who "set fire to the training facility" as they were leaving.
That narrative of events was starkly rebuffed by Ukraine, whose envoy said it was replete with "lies," and claimed Russian forces have already killed "several" plant staffers, and have not allowed any shift changes among employees that remain since Thursday.
"Every day provides us with newer and newer evidence that it is not only Ukraine under Russian attack. It is Europe. It is the entire world. It is humanity. And finally it is the future of the next generations," said Sergiy Kyslytsya.
Kyslytsya said that Russia has increasingly turned to overt "war crimes and crimes against humanity" after it faced unexpected resistance from Ukrainians to its invasion, with residential areas increasingly "being ruined by Russian bombs, shells and missiles."
Russia's war on Ukraine, which began on Feb. 24, has been met with international outrage, with the EU, US, and UK, among others, implementing tough financial sanctions on Moscow.
More than 1.2 million people have fled Ukraine to neighboring countries, according to the UN refugee agency.