The International Atomic Energy Agency (IAEA) is increasingly concerned about the welfare of Ukrainian staff at the Russian-held Zaporizhzhia nuclear power plant in Ukraine, Europe's largest, it said on Friday, adding that it must go there as soon as possible.

"The IAEA is aware of recent reports in the media and elsewhere indicating a deteriorating situation for Ukrainian staff at the country's largest nuclear power plant," the IAEA said in a statement.