Ministers face increasing questions over claims new nuclear power stations will be funded by the industry itself.
Some Labour MPs are suspicious of the subsidy claims
Industry secretary Alastair Darling says any investment in replacing nuclear capacity will be funded by the private sector, rather than government.
However, a stream of Labour MPs fear ministers may offer subsidies to the industry, particularly if it gets into financial difficulties.
Mr Darling says nuclear power is needed to help meet future UK energy needs.
He gave the go-ahead for a new wave of nuclear power stations during his statement to MPs on Tuesday.
Nuclear power accounts for 20% of the UK's electricity, but that is due to fall to 6% as all but one of the ageing plants shut down over the next 20 years.
Mr Darling said new nuclear power stations could make a "significant contribution" to meeting the UK's energy goals over the next 30 to 40 years.
He said: "It will be for the private sector to initiate, fund, construct and operate new nuclear plants and cover the cost of decommissioning and their full share of long-term waste management costs."
However, Elliot Morley, who was a minister in the Department of the Environment when the last Energy Review came out in 2003, was sceptical.
He said he welcomed Mr Darling's "very clear statement" that there "will be no public subsidies".
Labouring the point?
"But you well know, as I do, that there's been a history of nuclear sectors going bankrupt over the years," he said.
"Would you consider asking for a bond on new investment to cover that decommissioning and nuclear waste charges?"
Mr Darling said problems in the past were caused by people who failed to make the right calculations.
Labour left-winger Jeremy Corbyn pressed a little further: "Can you assure the House that there is going to be no subsidy whatsoever for the nuclear industry in the construction, operation or waste management or disposal as a result of this white paper?"
Mr Darling said he had answered this point and suggested the MP look at the Energy Review.
'Unequivocal answer' needed
Labour's Rob Marris wanted an assurance that there would be no "indirect subsidies" given, such as guaranteed prices, purchases or insurance cover.
The minister said there would be no guaranteed prices, although EU rules required some insurance.
The SNP's Michael Weir wanted an "unequivocal answer": "Does a 'full share' of the long term waste costs mean 100% - yes or no?"
Mr Darling said he had nothing to add to what he had said in his statement to MPs.
Labour's Gordon Prentice asked if the private sector would bear the whole cost of private security at nuclear plants.
Mr Darling replied: "I said that anyone coming forward with proposals to build nuclear power stations has to be responsible for meeting the costs of building, operating, maintaining and the decommissioning."