Since the conflict's start IAEA chief Grossi has warned of the potential for a nuclear accident at the plant, which he has previously visited twice and where a permanent IAEA team is based.

Sitting on the Dnipro river, the Russian-held Kakhovka dam, which was breached last week in an incident blamed by Kyiv on Moscow, forms a reservoir that provides the cooling water for the Russian-occupied plant.

The IAEA has warned that the Kakhovka dam disaster which claimed at least 10 lives and has left dozens missing further "(complicated) an already precarious nuclear safety and security situation at the" plant.

"On my way to Ukraine to meet President" Volodymyr Zelensky, tweeted Grossi on Monday with a picture of him and his team leaving Vienna where the IAEA headquarters is based.

"I will present a programme of assistance in the aftermath of the catastrophic Nova Kakhovka dam flooding," Grossi said.

"I will assess the situation at Zaporizhzhia nuclear power plant," and "conduct a rotation of ISAMZ," he added referring to the IAEA's Support and Assistance Mission to Zaporizhzhia (ISAMZ), "with a strengthened team".

On Sunday Grossi repeated his demand for full access to the plant for IAEA experts to measure the reservoir's water levels and produce an "independent" evaluation.

They will "clarify the reason for a significant discrepancy between different measurements of the height of the reservoir that is supplying water to cool the facility's six reactors and spent fuel storage", Grossi said.