To ask the Secretary of State for Defence what his most recent estimate is of the cost to the public purse of the Trident replacement programme. (275708)

Our current estimate, published in the December 2006 White Paper “The Future of the UK’s Nuclear Deterrent” (Cm 6994), is that the total procurement costs of the successor deterrent capability will be in the region of £15-£20 billion, at 2006-07 prices, for a four-boat fleet. This comprises £11-14 billion for the submarines, £2-3 billion for the possible refurbishment or replacement of the warhead and £2-3 billion for infrastructure. These costs are being refined as experts continue to engage in detailed discussion with industry.