Dr Julian Lewis: Does the Prime Minister agree that the gravest threat to Western interests and safety would be al-Qaeda getting its hands on Syria’s stocks of chemical weapons of mass destruction? Does he think that arming the rebels would make that outcome more or less likely?

[The Prime Minister: My hon. Friend is right to point to the danger of having extremists in Syria who have weapons and the intent to get hold of chemical weapons. We must ask ourselves how we have got to that point because they already have weapons and that intent. The extremist element of the opposition has become too strong, so our aim should be to reduce its strength. That is why we agreed at the G8 that part of the programme must be to expel extremists on all sides from Syria – that is the absolute key.

I say to those who see dangers, quite rightly, in engaging in any efforts to help Syria that we have got to the point of extremists having arms, ill intent and the desire to get hold of chemical weapons while there has been a deficit of engagement from countries that want Syria to take the right path rather than the wrong path. As I have said, we have not decided to arm the rebels, but are working with the opposition in the ways that I have described. We are working with the Americans and the French. I am sure that being engaged and being positive about what Britain can achieve with its partners is the right approach to reducing the dangers, rather than increasing them.]