The Zaporizhzhia nuclear power plant is seen in the background of the shallow Kakhovka Reservoir after the dam collapse, in Energodar, Ukraine, June 9, 2023. (PHOTO / AP)

MOSCOW/KYIV — The UN atomic watchdog said on Sunday it needs wider access around the Zaporizhzhia nuclear plant to check "a significant discrepancy "in water level data at the breached Kakhovka dam used for cooling the plant's reactors.

International Atomic Energy Agency head Rafael Grossi, who is to visit the plant this week, said that measurements the agency received from the inlet of the plant showed that the dam's water levels were stable for about a day over the weekend.

"However, the height is reportedly continuing to fall elsewhere in the huge reservoir, causing a possible difference of about 2 meters," Grossi said in a statement.

"The height of the water level is a key parameter for the continued operability of the water pumps."

The destruction of the Kakhovka hydropower dam in Kherson last week has flooded towns downstream, forcing thousands of people out of their homes. The water from the reservoir is used to cool the facility's six reactors and spent fuel storage, the IAEA said.

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"It is possible that this discrepancy in the measured levels is caused by an isolated body of water separated from the larger body of the reservoir," Grossi said in the statement. "But we will only be able to know when we gain access to the thermal power plant."

Ukrainian emergency workers wearing radiation protection suits attend training in Zaporizhzhia, Ukraine, June 7, 2023. (PHOTO / AP)

On the battlefield, Ukraine's top military command said on Monday its forces were engaged in heavy battles in front-line hot spots, a day after Kyiv said it had made the first modest gains in reclaiming territory from Russia as part of its counteroffensive

Grossi said the thermal power plant "plays a key role for the safety and security of the nuclear power plant a few kilometers away," hence the need for access and independent assessment.

Acting governor of the Kherson region Vladimir Saldo said on Sunday the number of hospitalized individuals in the Kherson region has now reached 77, noting they are receiving necessary medical assistance in local healthcare facilities.

Evacuations continued in the flood-affected areas of the Kherson region. As of Saturday, nearly 7,000 people have been evacuated from the flooded territories.

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Efforts are currently underway in Kakhovka to mitigate the consequences of the disaster, said Saldo.

On the battlefield, Ukraine's top military command said on Monday its forces were engaged in heavy battles in front-line hot spots, a day after Kyiv said it had made the first modest gains in reclaiming territory from Russia as part of its counteroffensive.

Ukraine said on Sunday its troops had made advances on three villages in Donetsk: Blahodatne, Neskuchne and Makarivka.

The claims could not be independently verified and there was no immediate comment from Russian officials.

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Both sides have said their forces had inflicted heavy personnel and equipment losses on the other side over the past week when Ukraine's counteroffensive was taking shape.

Russian President Vladimir Putin said on Friday that Ukraine had failed to breach Russian defenses, while his defense ministry said it had destroyed several main battle Leopard tanks and other equipment that Ukraine had received from the West.