Two ships, the Caloosahatchee and Canisteo, have already arrived despite fierce protests from green groups. Two more - the Canopus and Compass Island - will soon join them.

Campaigners say toxic chemicals and asbestos make the ships, originally destined to be scrapped in a Hartlepool breaker's yard, a health and environment threat.

But local MP Peter Mandelson said the fears were based on "misinformation" and the vessels should be dismantled as planned by Able UK.

He said: "There is no cargo of oil or chemicals, toxic or otherwise. There is no more than the usual amount of asbestos you get in all such old structures. They pose no danger to Hartlepool. They are not located near any centre of population."

Meanwhile, bosses from a Turkish yard arrived last week in London to win the contract to dismantle HMS Intrepid.

As it contains 40 tonnes of asbestos, this technically makes it illegal to scrap under Turkish law.

However, two years ago two other ships - the Royal Fleet Auxiliary tankers Olwen and Olna - were sent to Turkey to be scrapped, then turned back by its environment ministry because of the hazardous waste, including asbestos and PCBs, on board.

The ships, then under a British flag, were sailed to Greece and re-registered under the names Kea and the Kos. They were transferred to the Comoros islands, a flag of convenience off the coast of Africa, then sailed to India, where they were beached and broken up by hand by workers with no access to protective clothing or masks.

Exporting ships from developed countries to developing countries without removing all contaminants first is illegal under the Basle Convention, to which the UK is a party. The Ministry of Defence admitted that the ships had ended up in India but claimed the hazardous materials had been removed in Greece.

Their colleagues in the Department for Environment said it would be too dangerous for the US ghost fleet vessels to attempt a return crossing of the Atlantic at this time of year.

However, in a statement, the DoE added: "The US authorities accept that the four ships will have to return to the US next spring unless environmentally suitable and legally acceptable methods for their disposal have by then been found."

Friends of the Earth accused the Government of "being in a right mess" over the issue.

Spokeswoman Elaine Gilligan added: "The Government now has to keep its promise that on a long-term basis these ships have to go back to the States, to demonstrate they are standing up for the people of Teesside and the environment and environmental laws."

Article Link: Ghost fleet row takes new twist