KYIV, Ukraine (AP) — The largest nuclear power plant in Europe faces “a relatively dangerous situation” after a dam burst in Ukraine and Kyiv launches a counteroffensive to retake ground occupied by Russia, the head of the United Nations nuclear watchdog said Tuesday.

Rafael Moreno Grossi, the head of the International Atomic Energy Agency, spoke to journalists in Kyiv just before leaving on a trip to the Zaporizhzhia nuclear power plant. That plant has been repeatedly in the crossfire since Russia launched its war on Ukraine in February 2022 and seized the facility shortly after.

Grossi said he had met Ukrainian President Volodymyr Zelenskyy to discuss the situation affecting the plant, which grew more serious after the Kakhovka Dam burst last week. The dam, further down the Dnieper River, helped keep water in a reservoir that cools the plant's reactors. Ukraine has said Russia blew up the dam, something denied by Moscow, though analysts say the flood likely disrupted Kyiv's counteroffensive plans.

Grossi said the level of the reservoir that feeds the plant is dropping “quite steadily” but that it didn’t represent an “immediate danger.”

“It is a serious situation because you are limited to the water you have there,” Grossi said. “If there was a break in the gates that contain this water or anything like this, you would really lose all your cooling capacity.”

Ukraine recently said it hoped to put the last functioning reactor into a cold shutdown. That’s a process in which all control rods are inserted into the reactor core to stop the nuclear fission reaction and generation of heat and pressure. Already, five of the plant's six reactors are in a cold shutdown.

When asked about Ukraine's plans, Grossi noted that Russia controlled the plant and that it represented “yet again, another unwanted situation deriving from this anomalous situation.” Ukrainian workers still run the plant, though under an armed Russian military presence. The IAEA has a team at the plant, and Grossi said its members would be swapped out during his trip.

Asked about the Ukrainian counteroffensive, Grossi said he was “very concerned” about the plant potentially getting caught again in open warfare.

“There is active combat. So we are worrying that there could be, I mean, obviously mathematically, the possibilities of a hit,” he said.

Grossi stressed the IAEA hadn’t yet “seen any heavy military equipment” from the Russians at the plant when asked about Ukrainian fears the plant could be wired with explosives.

“There shouldn’t be any military equipment or artillery or amounts of ammunition, an amount that could compromise the security of the plant," Grossi said. "We do not have any indication at this point. But it could not be excluded.”

___

Follow Jon Gambrell on Twitter at www.twitter.com/jongambrellAP ___

Follow AP’s coverage of the war in Ukraine at https://apnews.com/hub/russia-ukraine