A senior official of Rivne nuclear power plant said on condition of anonymity that 1.3 cubic meters of water for cooling the reactor leaked due to pipe break. The leakage was restricted in an enclosed area with no spillover.
An announcement from Ukraine's state unclear power company Energoatom said the leakage "did not exceed permitted norms" and "the reactor was stopped."
"No increase of radioactivity was registered at or near the plant," it said.
Ukraine is heavily dependant on nuclear energy with half of its electricity generated by nuclear power plant despite having experienced Chernobyl reactor explosion in 1986.