Russia used more than 200 missiles and drones in Monday's attack on energy facilities, Ukrainian officials said.
"The Russian Federation continues to deliberately target Ukraine's energy infrastructure, intending to disrupt the operation of the country's nuclear power plants, which provide most of Ukraine's electricity," the Ukrainian mission to the UN nuclear watchdog said in a note on Thursday.
"Russian attacks pose a significant risk to the stable operation of nuclear facilities in Ukraine and the safety of millions of people."
Russia, which began its full-scale invasion in February 2022, stepped up attacks on Ukraine's power grid in March in what Kyiv said looked like a concerted effort to degrade the system before winter.
Ukraine's mission to the IAEA said Monday's attack was intended to paralyze the operation of power facilities.
"It is a deliberate decision by the Putin regime to threaten the world with nuclear catastrophe," Andriy Yermak, President Volodymyr Zelenskyy's chief of staff, said on Telegram messenger.
IAEA concern
Ukrainian officials have said Ukraine has lost about half its power-generating capacity during the war, and most of its power needs are now covered by electricity produced by three Ukrainian nuclear power plants.
Ukraine's Zaporizhzhia nuclear power plant, Europe's largest, is occupied by Russian forces and out of operation.
The IAEA has urged both sides to refrain from fighting around nuclear plants to avoid a catastrophic incident, and IAEA chief Rafael Grossi said after visiting Russia's Kursk nuclear power plant on Tuesday that there was a risk of a nuclear accident there.
Russia says the plant has been attacked by Ukrainian forces following a Ukrainian incursion into Russian territory this month. Ukraine has yet to respond to the accusations.
