In March there were protests at the transport of waste from France

It is the first German waste to go to the UK since the previous Christian Democrat-led Government halted all nuclear shipments in 1998, after radioactive contamination was discovered on the outside of the containers.

The new delivery has focused attention once again on an activity many within the German Government and the industry have begun to question.

Big money

The government wants to end nuclear reprocessing by 2005 but will allow shipments until then. The object of reprocessing is to separate out plutonium and uranium from used nuclear fuel rods - in theory to reuse the stuff as fuel.

British Nuclear Fuels (BNFL), which owns the Thorp reprocessing plant at Sellafield, says the German reprocessing business has netted them �1bn over the last 20 years. Germany work accounts for 10% of their orders, making it their largest European customer.

The question is whether it makes sense to operate a huge and expensive facility to separate out materials that have no economic value

Mycle Schneider, energy consultant

It was an appealing idea when the new generation of fast breeder reactors burning plutonium seemed a viable prospect. But the programme has been scrapped and uranium - once thought to be in short supply - has turned out to be far from scarce. Its value has plunged on the world market, destroying the economic argument for reprocessing. It is simply cheaper to use fresh uranium.

The real reason nuclear waste is sent to Britain and France is to "buy time", said Mycle Schneider of the Paris-based energy consultancy WISE which has worked for the German Government .

Memories of the Chernobyl disaster are still strong

He pointed to a 20-year gap between sending used fuel rods abroad to the French reprocessing plant at La Hague and getting back the real waste for final storage.

British Nuclear Fuels said the plutonium separated out by reprocessing would be "stored safely and securely at Sellafield for future customer use".

But officials at the German power plants have confirmed there are no fixed plans to take the products back. BNFL maintains it is in the contracts that Germany must take it back eventually.

Asked whether his company still believed in nuclear reprocessing, one senior manager at a German power station told the BBC: "We have never believed in it".

Legal bind

Environmentalists have always maintained the waste should go straight into permanent storage without being reprocessed.

The German Government is committed to phasing out nuclear power within 30 years, but it is allowing the German power generators to honour existing contracts with BNFL, and with Cogema in France.

BNFL predicts a further 40 shipments from Germany to the UK. If past experience is anything to go by, each shipment is likely to be accompanied, on the German leg of its journey at least, by angry protests.

It is all very embarrassing for Chancellor Schroeder's Red-Green coalition in Berlin. The reason for the continuation is simple - Germany does not have the storage capacity for its waste.

The waste is being sent to Britain because the contracts have to be honoured. It would cost German utilities too much to break them, even if they too have begun to question why they are doing it.