“I will continue to be worried about the plant until we have a situation which is more stable,” he told reporters after leaving the plant.

Grossi said IAEA experts toured the entire site, including control rooms, emergency systems and diesel generators, and met with the plant’s Ukrainian staff, who have been operating the plant under Russian control since March.

Ukraine’s state nuclear company, Energoatom, claimed that the IAEA mission mission had not been allowed to enter the plant’s crisis center, where Ukraine says Russian troops are stationed, and would struggle to make an impartial assessment.

“The (Russian) occupiers lie, distort the facts and evidence that testify to their shelling of the power plant, as well as the consequences of damage to the infrastructure,” it said.

In his nightly video address on Thursday, Ukrainian President Volodymyr Zelensky criticized the UN mission for failing to ensure the presence of independent Ukrainian and international journalists during their visit, which he said had been promised to him, and for not calling for the complete demilitarization of the site.

But speaking to an Italian forum on Friday, Zelensky sounded a more hopeful note, saying that the UN could still have a role to play despite the difficulties.

Meanwhile, Russian Defense Minister Sergei Shoigu accused Ukraine of “nuclear terrorism” and rejected assertions by Kyiv and the West that Russia had deployed heavy weapons at the plant.

“We do not have heavy weapons on the territory of the nuclear power plant or in the surrounding areas. I hope the International Atomic Energy Agency mission will be convinced of this,” Shoigu said in remarks published by the defense ministry.

Shoigu on Friday doubled down on Moscow’s insistence that Kyiv would carry the responsibility for any escalation at the site

Shoigu said Kyiv was “creating a real threat of nuclear catastrophe” and using Western-supplied weapons to attack the plant.

He said Ukraine had fired 120 artillery shells and launched 16 “kamikaze” drone attacks over the last six weeks.

“This is nothing short of nuclear terrorism,” Shoigu added, as he also accused the United States and European Union of “encouraging such reckless actions.”

One of the plant’s reactors was forced to shut down on Thursday due to shelling.

Russia’s ambassador to international institutions in Vienna said two IAEA inspectors would stay at the Zaporizhzhia plant on a permanent basis, the RIA Novosti news agency on Friday.

The IAEA’s Grossi said on his return to Ukrainian-held territory on Thursday that his experts would stay at the facility.

“We are not going anywhere. The IAEA is now there, it is at the plant and it is not moving – it’s going to stay there,” Grossi told reporters once he had crossed back into Ukrainian-held territory.

Those experts, he said, would provide what he called an impartial, neutral, technically sound assessment of what was happening on the ground.

With Post Wires