"CoRWM considers geological disposal to be the best available approach for the long-term management of all the material categorised as waste," it said at the end of a three-day meeting in the south coast resort of Brighton.

The decision means putting the nuclear waste beyond retrieval forever rather than securing it but making it accessible for future generations should technological advances make it useable.

But the committee, noting that the process of identifying suitable sites, obtaining local consent and planning permission and then constructing the stores could take decades, also said the life of interim storage sites needed to be prolonged.

The draft decision came the day after the 20th anniversary of the explosion at the Chernobyl nuclear plant in Ukraine that spewed radioactive dust across much of northern Europe.

CoRWM, made up of academics, economists and nuclear experts, has been working for two years assessing how best to deal with waste from Britain's civil nuclear programme that remains toxic for thousands of years.

NUCLEAR DECISION

Its recommendation has been eagerly awaited by the government as it decides whether to go ahead with a new generation of nuclear power plants to plug the country's looming electricity gap as it has to shut down many of the ageing nuclear and coal-fired stations.

CoRWM made no recommendation on whether the government should opt to build new nuclear plants.

A report by the Department of the Environment, Food and Rural Affairs in 2001 put the total volume from all sources of nuclear waste in Britain at 1.75 million cubic metres.

CoRWM said this would rise sharply as all but one of the country's ageing nuclear power plants were closed, dismantled and disposed of over the next decade.

The Nuclear Decommissioning Authority, set up in 2005 to oversee the dismantling of Britain's old nuclear power stations, calculated this year that the cleanup costs of all the civil nuclear sites would be up to 70 billion pounds (US$125 billion).