[John Woodcock: The Prime Minister says that savings can be made in this Parliament by delaying Trident, but can he say what the increased cost overall to the deterrent programme will be of this delay and how this needless risk and uncertainty are showing leadership in the long-term interests of the country?

The Prime Minister: I know that the hon. Gentleman has a strong constituency interest in this matter. I can tell him that overall the cost will be lower this was a value-for-money exercise. We are driving costs out of the programme, and overall we believe that it will be less expensive. Further good news is that the Astute class submarines are going ahead. Obviously he will have a tortured time ahead as he considers the fact that this Prime Minister and Government support the Trident replacement when his own party is going a bit soft on it.]

Dr Julian Lewis: My right hon. Friend has it in his power to secure the future of the nuclear deterrent until 2055 by holding the vital vote and making the main gate contract decisions in this Parliament, not the next one. He could do that at no extra cost, even if he wishes to delay the introduction of the system. Will he explain his reason for delaying this vital vote into the next Parliament, other than to make our ultimate deterrent a political gambling chip to satisfy the Liberal Democrats?

[The Prime Minister: I worked with my hon. Friend for many, many years, and I know that he takes an extremely close and professional interest in this matter. I remember he did it when there was not a single supporter of nuclear deterrence on the Labour Benches. He did a great service to the country. However, I would make two points to him: first, the military advice is that we need to go through the main gate in 2016, not earlier. I would also like to make another, slightly more frivolous point: I am not as lacking in confidence as he is that there will be plenty of supporters of Britain's strong and independent nuclear deterrent in the next Parliament.

Ms Gisela Stuart: Given that the Prime Minister, in his previous answer, cast doubt on the Labour Party's commitment to Trident, and given that we know that his coalition partners are against it, may I return to the question he was just asked? Why is he afraid to put this to a vote before 2015?

The Prime Minister: I really think that I have answered the question. The military advice is that 2016 is when we need to go through the main gate. We are going through the initial gate this year. We now have the Backbench Business Committee, so if anybody wants to hold a vote in this Parliament, they can do so, to check that we are going through the initial gate, which we are steaming through this year. I question the Opposition's position, because the Leader of the Party said throughout the leadership election:

“I have been clear … I believe the right approach is to include the decision about the replacement of Trident in the … Defence Review”.

He is therefore not automatically committed to the full replacement of Trident, so perhaps the hon. Lady ought to have a word with him and put him right on that.]