VIENNA (Reuters) - The backup power line at the Russian-held Zaporizhzhia power plant (ZNPP) in Ukraine has been disconnected deliberately to extinguish a fire, but it was not damaged, the U.N. nuclear watchdog said on Monday, citing information supplied by Ukraine.
Both sides in the war have accused each other of risking nuclear catastrophe by shelling near the plant in southern Ukraine, captured by Russia but still operated by Ukrainian engineers.
The last of four regular, 750-kilovolt (kV) power lines providing electricity essential to the plant's safety was disconnected on Friday. The International Atomic Energy Agency said Ukrainian staff at the plant told its experts that they plan to repair it but that it would take several days.
The 330-kV backup line can supply Zaporizhzhia with power from a nearby coal-fired plant. After the fourth regular line was disconnected, however, it delivered electricity from Zaporizhzhia to the grid, the IAEA said.
"The ZNPP continues to receive the electricity it needs for safety from its sole operating reactor," the International Atomic Energy Agency said in a statement. "Ukraine informed (the) IAEA that this backup line will be re-connected once the fire has been extinguished."
Once the backup line is switched on again the operating reactor will be reconnected to the grid, the IAEA said. Zaporizhzhia has six reactors and is Europe's biggest nuclear power plant.
On Monday, the IAEA presence at the plant was reduced to two staff members from six. The IAEA plans to maintain the current presence in the longer term.
IAEA chief Rafael Grossi will issue a report on Ukraine, including the plant, on Tuesday and then brief the United Nations Security Council, the IAEA said.
(Reporting by Francois Murphy; Editing by Lisa Shumaker)