The Ministry of Defence (MoD) is planning to spend £4.2 billion on replacing the Trident nuclear weapons system before the UK parliament has given it the go-ahead, according to a report from the government's National Audit Office (NAO).


The money is being spent on designing new submarines, reactors and missile compartments ahead of a long-promised decision on Trident replacement by MPs in 2016, after this year's UK general election. Previous reports have suggested that around £2bn or £3bn would be incurred before the decision was taken.

Opposition politicians and campaigners have condemned the MoD for pre-empting a democratic decision on whether or not the UK should continue to rely on weapons of mass destruction. The MoD says it has always been transparent about the costs "whilst protecting our commercial position".

The NAO report also reveals that the MoD has underestimated the cost of upgrading the nuclear reactors that power Trident submarines by £151 million. This was because it had to master 40 new manufacturing techniques while coping with an acute shortage of nuclear engineers.

The revelations raised very serious questions for the MoD, warned the SNP Westminster leader and defence spokesman, Angus Robertson MP. "Costs are spiralling out of control before MPs have even had a chance to vote on renewal," he told the Sunday Herald.

"It is utterly unacceptable that over £4 billion will be blown on replacing Trident nuclear weapons before parliament actually decides on whether or not to even give it the go ahead. In no other democracy, at a time of deep austerity and cuts, would money be spent on committing to such a massive project without consulting parliamentarians."

According to the NAO report, £2.1bn has already been spent on the Trident successor project, leaving another £2.1bn still to be spent over the next two years. But in a parliamentary answer to Robertson last week, the MoD wouldn't break that down into annual expenditure, arguing that to do so "would prejudice commercial interests".

Robertson criticised the MoD for keeping the annual figures secret. "Bills could be piling up for underestimates as it becomes increasingly clear that Trident renewal is completely out of control," he said.

The £151m underestimate on the upgraded submarine reactor was "alarming", he added. "If they've underestimated the complexity of designing a nuclear reactor, it bodes ill for the weapons costs."

The Green MSP, Patrick Harvie, argued that it was "absurd" to spend such large sums of money before a decision has been made. "It appears the Treasury is only too happy to grease the wheels for the renewal of an unsafe, immoral system of mass slaughter," he said.

"The Westminster consensus must be overturned so we can divert public funds away from nuclear weapons and towards new jobs and tackling poverty and inequality in our communities."

John Ainslie, coordinator of the Scottish Campaign for Nuclear Disarmament, called for an end to the needless waste of precious resources on Trident. "The UK government is spending eye-watering amounts of money on something which they haven't yet decided to buy," he said.

"They clearly have no control over the spiraling cost of building reactors for the new submarines. The MoD started work on a new reactor without appreciating the scale of the task."

The NAO report brings together expenditure on what are termed the "concept" and "assessment" phases of the Trident successor project. It says £854 million is being spent on conceiving future submarines, reactors and missile compartments, and £3,319 million on assessing them (see table below).

The MoD confirmed the NAO figures. "We have been transparent with the successor costs whilst protecting our commercial position, and have always been clear that we expect to spend £900 million on the concept phase and £3.3 billion on the assessment phase," said an MoD spokeswoman.

The MoD accepted that there was a nuclear skills shortage, but highlighted a series of initiatives being taken to tackle the problem. It stressed that no submarines would go to sea without the minimum complement of qualified staff required to operate the boat safely.

The MoD spokeswoman added: "The government is working hard to tackle the skills gap, and last year announced the intention to open a new elite college offering skills training for the nuclear power sector, alongside £8 million of funding to train future nuclear engineers."