An inspection of Ukrainian nuclear plants found no military equipment, debunking a claim from Russia, International Atomic Energy Agency (IAEA) chief Rafael Grossi told the European Parliament on Tuesday.

Grossi's remarks came the day after Russia's foreign intelligence service accused Ukraine of storing Western-supplied arms at nuclear power stations across the country - an allegation dismissed as untrue by a senior Ukrainian official.

Grossi told the European Parliament that his agency had established a permanent presence at all Ukrainian nuclear facilities and he had ordered inspections on Tuesday to ascertain whether any of them contained military equipment.

"The result of those inspections was negative," he said.

He said this was the second time the IAEA had been able to "debunk accusations of illegal things and very dangerous things taking place in these facilities", citing previous accusations about the creation of a "dirty bomb".