LONDON Britain's defense ministry has not yet established the overall cost of replacing and maintaining its aging nuclear weapons system, it told Reuters, prompting opposition charges of mismanagement of a mega-project expected to be given the go-ahead this year.
In response to a request by Reuters about an estimate of the total price tag for the new Trident submarine fleet - Britain's sole nuclear weapons system - the ministry said it was still working on "policy options" and gave no overall figure.
The replacement of Trident, which was backed in principle by parliament in 2007 and is expected to be formally approved this year, has raised questions about national security as Britain heads for a referendum on European Union membership that may decide its future status on the world stage.
The Conservative government says the deterrent is vital to keep Britain safe in an increasingly hostile world, but some leading opposition figures say it is indefensible to commit a significant portion of the public purse to renewing the program at a time of deep austerity cuts.
This makes the precise cost of replacing Trident a politically charged issue.
The government has indicated the price tag for replacing the fleet has risen since 2007 but has not given a full cost over its expected 30-year life. Calculations by Reuters and a Conservative lawmaker suggest it could reach 167 billion pounds.
"The department does not hold a cost forecast for the whole capability," the defense ministry said in response to the Reuters request under the Freedom of Information Act asking for the estimated cost of replacing Trident over 30 years.
"The government needs a safe space away from the public gaze to allow it to consider policy options for delivering the deterrent in the most cost-effective way, unfettered from public comment about the affordability of particular policy options, some of which many not be at a mature stage of development."
It did not elaborate on the policy options.
The main opposition Labour Party criticized the government for refusing to offer any detail over what is called the "Successor program".
Its defense spokeswoman, Emily Thornberry, said it was clear costs were "out of control" at a time when the Chancellor, George Osborne, is struggling to balance his budget.
"It is astonishing that the Ministry of Defense still cannot say what the total costs of the Successor program will be, despite the massive implications of this program for government spending in the coming decades," said Thornberry, who is leading Labour's Defense Policy Review and has in the past been a critic of replacing Trident.
She accused the government of a lack of transparency over the costs and arrogance in demanding more time to develop policy when it has already spent 10 years and "more than 3 billion pounds".
"That arrogant refusal to account to parliament and the public is simply unacceptable," she said in a statement.
"It is high time that the National Audit Office (the public spending watchdog) and the Public Accounts Committee conducted full investigations into the costs and management of the Successor program, and forced the Ministry of Defense to start answering the legitimate questions they are being asked."
Labour is deeply divided over whether to replace Trident - its leader opposes it but many in the party believe it is necessary. It is however keen to put more pressure on a government torn by divisions over EU membership and forced after just two days to abandon welfare cuts in its 2016 budget.
The Ministry of Defense said: "The government is committed to maintaining the UK's independent nuclear deterrent – the ultimate guarantee of our nation's safety."
The ministry has been working on replacing Trident for a decade and has tracked the rising costs in speeches to parliament, which have been criticized by opposition MPs for being too vague. Initially, in 2006, the cost of producing the submarine and warheads was put at around 15-20 billion pounds.
In its response to Reuters, the ministry gave some of its latest costs that had already made public: the replacement of Trident would cost 31 billion pounds to produce the four submarines, with a contingency of 10 billion pounds, and another 3.9 billion pounds had been already allocated to their design.
The ministry also said in its statement that in-service costs over its lifetime would be about 6 percent of the annual defense budget.
According to the calculations by Reuters and a Tory MP last year based on assumptions the defense budget would remain largely the same as now, that would take the total to 167 billion pounds over 32 years - a sum that has spurred calls by the Scottish National Party to scrap the fleet.
But the ministry said it could not provide any detail of the costs for the nuclear warheads, support services infrastructure and running costs, as the scheme involved projects which formed parts of other defense capabilities.
"The department does not hold information in a form that would allow for a 30-year cost forecast for the nuclear deterrent capability to be easily calculated," it said.
Ministers have said it is one of the government's biggest schemes ever, and that building the submarines alone would cost about twice as much as London's 15-billion-pound new railway link, currently the largest infrastructure project in Europe.
The government is expected to put the decision on whether to replace Trident to a parliamentary debate and vote later this year, when the project is set to get the green light. But it has been accused by opposition politicians of delaying the debate to avoid any contentious issues before the June 23 EU referendum.
Last month, U.S. Defense Secretary Ash Carter said Britain needed to renew Trident if it was to maintain its "outsized" role in world affairs.
Malcolm Chalmers, deputy director-general for defense and security think-tank RUSI, agreed and underlined the difficulty in coming up with long-term cost estimates as they could be "radically different", depending on what assumptions were made.
(Editing by Pravin Char)