MOSCOW: The UN rejected Russian accusations that it is preventing a visit by nuclear experts to the Zaporizhzhya nuclear  plant in Ukraine, amid reports of more shelling and explosions there on Monday.

For weeks, Russia and Ukraine have been accusing one another of shooting on the biggest nuclear power station in Europe, possibly causing a catastrophic disaster.

The facility in southern Ukraine is controlled by Kremlin forces, and Russian Defence Minister Sergei Shoigu spoke with UN Secretary General Antonio Guterres on the subject on Monday, according to dpa news agency.

Stephane Dujarric, a spokesperson for the United Nation, said in New York that it was "simply not the case" that staff from the International Atomic Energy Agency (IAEA) were being delayed from travelling.

He added that the Vienna-based IAEA nuclear organisation functions independently of the UN and that "the UN Secretariat has no ability to stop or cancel" the visit. According to Dujarric, the UN has "the security, the logistics capacity" in Ukraine to assist the IAEA inspectors' trip to Zaporizhzhya.

But an agreement with Russia and Ukraine is required, he said.

There have been differences of opinion on different issues, including the potential transit path for IAEA inspectors. A mission that would only travel through Russian-occupied territory, such as the Crimea or another route over the Russian-Ukrainian border, would not be permitted by Ukraine.

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