Foreign ministry spokeswoman Maria Zakharova accused Kyiv of seeking to create "conditions for a nuclear disaster, not only on its territory, but throughout Europe."

The Zaporizhzhia plant in southeast Ukraine is the largest in Europe. Russian troops took control of it in March, early in their Ukraine offensive.

Zakharova said Ukrainian forces had fired on it twice this week -- on July 18 and July 20 -- from a drone.

She said the strike landed "just tens of metres" away from a reactor cooling tank.

"It was only by luck that this did not lead to damage to the equipment and to a man-made catastrophe," she said.

Moscow-installed authorities in the part of Zaporizhzhia region controlled by Russian troops accused Ukraine of "nuclear terrorism" and said they would appeal to the United Nations.

The UN's nuclear watchdog said last month that it was planning to visit the Zaporizhzhia nuclear plant, despite protests from Kyiv.