Russia's Foreign Minister Igor Ivanov says he believes Nato forces may be using weapons containing radioactivity against Yugoslavia.

"In a number of areas of Kosovo, experts have detected enhanced radiation levels in the atmosphere and on the ground," Mr Ivanov said.

"This gives grounds for thinking that Nato may be using new types of weapons against Yugoslavia, ones with radioactive components."

His suggestion echoes other unconfirmed reports that Nato aircraft are using munitions containing depleted uranium (DU).

The Ministry of Defence said it did not think DU weapons were being used by Nato.

But the Labour MP Tam Dalyell, who opposes the use of force against Yugoslavia, told BBC News Online he thought it was "more than possible".

The A-10 jets being used over Kosovo against tanks were also used to attack Iraqi forces in 1991.

During that war, the jets fired 30 mm rounds reinforced with DU, a waste product of the uranium enrichment process.

The substance is 1.7 times more dense than lead and is used in an alloy form in shells to make them better penetrate targets.

Danger for the region

John Catalinotto of the International Action Center in New York, set up by former US Attorney-General Ramsey Clark and others to oppose US military involvement around the world, said: "As the shell hits its target, it burns and releases uranium oxide into the air.

"The poisonous and radioactive uranium is most dangerous when inhaled into the body, where it will release radiation during the life of the person who inhaled it."

The IAC said the Pentagon's decision to use the A-10s in the conflict was "a danger to the people and environment of the entire Balkans".

And it claimed "solid scientific evidence" that DU residues in southern Iraq are responsible for a large increase in stillbirths, birth defects, childhood leukaemia and other cancers.

Iraq: Depleted uranium shells fired at tanks

Many allied troops who served in the 1991 war say they are victims of Gulf War Syndrome (GWS), characterised by chronic fatigue, weight loss, and defects in children born subsequently.

In February, 16 British Gulf War veterans said they had proof that they were suffering from radiation poisoning, which they thought could be a factor in GWS.

Doctors in Iraq say children there have been damaged by the same radiation.

But the US Defense Department said there was no evidence of a link between cancer and DU, which was no more radioactive than lead.

A report from the Ministry of Defence in London said last month that DU was unlikely to have contributed to GWS.

It said DU presented two hazards - a radiation and a chemical toxicity risk.