Replied to survey in April 2011:
"Thank you for contacting me with your views on Trident and the future of Britain's nuclear deterrent. As you know, this is a matter reserved to Westminster.
"The Ministry of Defence recently completed a long overdue Strategic Defence and Security Review (SDSR), the last one of which took place in 1998. This review analysed what kind of defence Britain requires for the future and therefore what the structure of our Armed Forces and supporting equipment should be.
"Alongside this review, and as agreed as part of the Liberal Democrats forming a coalition with the Conservatives, the UK Government conducted a Value for Money study of Trident and its planned replacement. The study concluded that significant savings could be made by reducing the number of missiles and warheads on each submarine and by extending the timeframe of deciding Trident's replacement.
"The SDSR also announced that the 'Main Gate' decision for Trident replacement - the point at which final contracts are signed and money committed - will be extended to 2016. This means there will be no final decision on Trident replacement until absolutely necessary and not during this Parliament. By extending the timetable for key decisions, Britain will not only save money in the short term, it will allow the opportunity to keep nuclear policy under review. This will allow more in-depth consideration of key cost-saving options like altering continuous at-sea patrols and extending the service life of Vanguard submarines and consideration of alternatives to the current plans for a successor programme.
"The devastating potential of nuclear weapons remains at the forefront of the Liberal Democrat thinking and as a party we are committed to working towards a world without these weapons. This will undoubtedly be an incremental process. Furthermore, it is crucial that any current British nuclear deterrent provide value for money and that all avenues and alternatives be fully explored. Please rest assured my party colleagues and I will continue to explore and argue the case for such alternative systems until they are given the full consideration they deserve.
"We remain opposed to the construction of new nuclear power stations in Scotland."