UN nuclear agency chief Rafael Grossi arrived on Tuesday at the Kursk nuclear power plant, which Moscow says has been repeatedly attacked by Ukrainian forces that are just 40 km (25 miles) away after carving out a slice of Russian territory.
Moscow and Kyiv have repeatedly blamed each other for drone and artillery attacks on the Russian-controlled Zaporizhzhia nuclear power plant in Ukraine. However, the Aug. 6 incursion by Ukrainian forces into Russia has put the spotlight on the Kursk plant - a major Soviet-era station.
President Vladimir Putin accused Ukraine on Thursday of trying to attack the Kursk plant, which has four Soviet graphite-moderated RBMK-1000 reactors - the same design as those at the Chornobyl nuclear plant, which in 1986 became the scene of the world's worst civilian nuclear disaster.
Ukraine has yet to respond to the accusations that it attacked the facility.