Russia's nuclear power operator Rosenergoatom said on Telegram that a "Ukrainian armed forces combat drone attempted to attack a cooling tower at the Novovoronezh Nuclear Power Plant" in central Russia in the night from Monday to Tuesday.

The International Atomic Energy Agency (IAEA) said it was informed by Russia that a drone hit the site.

There was "no impact on nuclear safety and no change in radiation levels" there, the IAEA said on X.

Agency head Rafael Grossi "reiterates that NPPs (nuclear power plants) must never be attacked," the post added.

Rosenergoatom said the drone "was suppressed by technical means" near the plant, causing it to detonate after colliding with the cooling tower.

"There were no damages or injuries," the operator said, adding the incident did not affect the plant's operations.

"This is another act of aggression by the Ukrainian Armed Forces against Russian nuclear power plants," Rosenergoatom added.

There was no immediate comment from Ukraine.

Kyiv has been ramping up retaliatory strikes on Russia's energy and oil infrastructure, in what it sees as a legitimate response to Moscow's offensive and its daily attacks on Ukrainian cities, which have at times left millions without heating and power.

Both Moscow and Kyiv have accused each other of attacking nuclear sites throughout the three-and-a-half year war, prompting fears of a nuclear incident.

Ukraine's southern Zaporizhzhia nuclear plant, which Russian forces captured shortly after invading in 2022, has been disconnected from the power grid for two weeks.

It now relies on backup electricity generators to maintain cooling and other safety systems.