Safety at Ukraine’s Zaporizhzhia nuclear power plant is deteriorating following a drone strike that hit a perimeter access road on Saturday, according to International Atomic Energy Agency director general Rafael Mariano Grossi.

The Russian management of the Zaporizhzhia nuclear power plant said a Ukraine drone dropped an explosive charge on a road used by staff, the TASS news agency reported earlier.

Russia has been in control of the Zaporizhzhia site, the largest nuclear power plant in Europe, since soon after it launched its full-scale invasion of Ukraine in February 2022.

The plant is dormant as Moscow and Kyiv have repeatedly accused each other of trying to sabotage its operations and endangering safety around the plant.

“Yet again we see an escalation of the nuclear safety and security dangers facing the … power plant,” Grossi said.

“I remain extremely concerned and reiterate my call for maximum restraint from all sides and for strict observance of the five concrete principles established for the protection of the plant,” he said.

The impact site was close to the essential cooling water sprinkler ponds and about 100 meters (109.3 yards) from the Dniprovska power line, the only remaining 750 kilovolt line providing a power supply to the plant, the IAEA said.

An IAEA team visited the area on Saturday and reported that the damage seemed to have been caused by a drone equipped with an explosive payload.

The report said there were no casualties and no impact on any nuclear power plant equipment. However, there was an impact to the road between the two main gates of the plant.

Moscow wants to discuss the attack on the Zaporizhzhia plant with the IAEA, Russia’s RIA news agency reported, citing Roman Ustinov, the acting Russian representative in Vienna.