British Nuclear Fuels (BNFL) has acknowledged that the Sellafield nuclear plant in Cumbria is to shift focus from reprocessing spent nuclear fuels to managing radioactive waste.
The Thorp plant reprocesses fuel from overseas
Its statement comes in response to a newspaper report which suggested that Sellafield's Thorp reprocessing plant - which converts spent fuel rods into uranium and plutonium - would close by 2010.
Closure would have both symbolic and practical implications for the future of the nuclear industry in Britain.
Nuclear reprocessing was once seen as the key to almost unlimited power generation.
Britain has built its nuclear industry largely on reprocessing waste for other countries - countries which may now have to reconsider the future of their own nuclear industries.
In its statement, the BNFL said its current order book of contracts extends to 2010 - but refused to confirm that was the date envisaged for the closure of Thorp's reprocessing activities.
"Although the focus of the Sellafield Site is shifting from commercial reprocessing to clean up and managing the historic legacy, BNFL has made it clear that all existing reprocessing contracts will be honoured," it said.
Any future role for Thorp, it said, will depend "upon the wishes of our customers, the Nuclear Decommissioning Authority (NDA) which will assume ownership of the site in 2005 and ultimately the sanction of government".
David Bonsor, acting chief executive of British Nuclear Fuels, told BBC News 24 that 2010 was "our current planning assumption".
He said: "If customers want business beyond 2010, then that's a decision for them to come to us and ask us for that business and we'll talk to the NDA."
The great hopes once invested in nuclear power generation from reprocessing have foundered on high relative costs, public fears about safety and proliferation, and difficulties disposing of highly radioactive waste.
BNFL itself has liabilities now estimated at £41bn - forcing it to relinquish ownership to the NDA.
There are two reprocessing plants at Sellafield - the Magnox reprocessing plant, for fuel from the first generation of British reactors, and Thorp, which opened as a nuclear reprocessing plant in 1994.
Martin Forward, spokesman for Cumbrians Opposed to a Radioactive Environment (Core), said the Thorpe plant was hailed as having a lifespan of at least 25-30 years.
He said: "We would be pleased if reprocessing stopped sooner than BNFL wanted it to and moved towards a clean-up, which is desperately needed.
"We are angry as well. When the plant was in the planning stage, BNFL said there was a massive amount of business out there, but the reality is that they have never managed to pick up more business for the plant."