During the massive attack in Ukraine on November 17, four substations of Ukrainian NPPs, identified by the International Atomic Energy Agency (IAEA) as important for nuclear safety, were damaged, the agency reported.

"Four of these substations and their power lines were impacted again by the attacks during the night of 16 November and early morning of 17 November, prompting Ukraine’s operating NPPs to reduce their power output as a precautionary measure," the agency reported on its website.

According to it, in recent days the NPPs gradually began to restore power lines and increase production, but reduced it again this morning as a precaution, and then restored it.

In addition, the agency indicated that on Thursday morning the Pivdennoukrainsk NPP disconnected from its two 750 kV power lines for maintenance and continued to receive electricity through backup systems.

"The growing instability of the power grid is a deepening source of concern for nuclear safety, affecting all the nuclear power plants," Director General Grossi said.

Before the latest attacks on Ukraine’s energy infrastructure, IAEA teams visited seven substations in September and October to assess the damage caused by the attacks in August, as part of their wider efforts to help the country ensure nuclear safety and security.

They "documented extensive damage to all the substations visited, concluding that the grid’s capability to provide a reliable off-site power supply to Ukrainian NPPs has been significantly reduced. Repairs and additional protective measures are being implemented by Ukraine," Director General Grossi told this week’s Board.

The IAEA teams present at the Khmelnytskyy, Rivne and Pivdennoukrainsk NPPs and the Chornobyl site reported that nuclear safety and security is being maintained despite the grid instability and the effects of the ongoing conflict, including a number of air raid alarms over the past week.