The level of safety at a Ukrainian nuclear plant under Russian occupation is a "red light blinking", the chief of an international nuclear agency has warned. 

The Zaporizhzhia nuclear plant in southern Ukraine was taken over by Russian forces amid the ongoing war in the country. 

The director-general of the International Atomic Energy Agency (IAEA) has claimed the organisation has not been able to gain access to the nuclear plant for repairs. 

Rafael Grossi told the Associated Press (AP) that the situation is not sustainable and that the IAEA needs access so inspectors can also re-establish a connection between the plant and the agency's Vienna-based headquarters. 

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The plant requires repairs but they have not been able to take place.

Mr Grossi said: "So the situation as I have described it, and I would repeat it today, is not sustainable as it is."

“So this is a pending issue. This is a red light blinking.”

He spoke in an interview on Wednesday, a day after meeting with Ukrainian President Volodymyr Zelensky about the issue.

“Understandably, my Ukrainian counterparts do not want the IAEA inspectors to go to one of their own facilities under the authority of a third power,” Mr Grossi said.

“I had a long conversation about this with President Zelensky last night, and it’s something that will still require consultations. We are not there yet.”

The IAEA chief continues to press Russia’s government for access to the Zaporizhzhia plant.

“I don’t see movement in that direction as we speak,” he said.

But he is meeting with the Russian side “soon”.

“There are two units that are active, in active operation, as you know, others that are in repairs or in cool down. And there are some activities, technical activities and also inspection activities that need to be performed,” Mr Grossi said.

With 15 reactors and one of the largest nuclear power capacities in the world, the war has essentially turned parts of Ukraine into a nuclear minefield.

Again and again since the invasion, nuclear experts have watched in alarm as Russian forces have come uncomfortably close to multiple nuclear plants in Ukraine.

A Chernobyl security worker told the AP that the Russians flew aircraft over the damaged reactor site and dug trenches in highly radioactive dirt.

On Monday, Russian cruise missiles flew over the Khmelnitsky nuclear plant in western Ukraine.

“There cannot be any military action in or around a nuclear power plant,” Mr Grossi said, adding that he has appealed to Russia about this.

“This is unprecedented to have a war unfolding amidst one of the world’s largest nuclear infrastructures, which, of course, makes for a number of fragile or weak points that could be, of course, exploited wittingly or unwittingly,” he added.

“So this requires a lot of activity on our side and co-operation. Co-operation from the Russian side. Understanding from the Ukrainian side so that we can avoid an accident.”