"We have got to recognise what the nature of the threat that we are dealing with is al-Qaeda and people who are related to al-Qaeda - and while I don't want to comment on the police investigation that is on-going, it is clear that we are dealing in general terms with people who are associated with al-Qaeda.

"It wants to make its point, its propaganda effort, by inflicting maximum damage, irrespective of religion, on civilian life. In any country - and we know al-Qaeda are operating in more than 60 countries - we can expect that they will use different forms of missile or weapon or different forms of activity, whether it is planes or cars, to inflict that damage."

"It's obvious that we have a group of people - not just in this country, but round the world - who are prepared at any time to inflict what they want to be maximum damage on civilians, irrespective of who the religion of these people who are killed or maimed are to be.

"And so, we will have to be constantly vigilant. We will have to be alert at all times. And I think the message that's got to come out from Britain, and from the British people, is that as one, we will not yield. We will not be intimidated and we will not allow anyone to undermine our British way of life."

"The police are in a fast-moving operation. They've made enormous progress in a very short period of time. When these attacks or these threats happen, the public, the police, the emergency services, the security services all come together and it makes me very proud that we have people in Britain who are prepared to respond with such professionalism and with such dedicated service."

"If in the long term we cannot separate the moderates from the extremists, and the extremists prey on young lives - both in this country and in other parts of the world - then we will see, culturally, a distancing of people with extreme views from the rest of the community.

"And that's why the cultural effort - almost similar to what happened in the Cold War in the 1940s, 1950s and 1960s, when we had to mount a propaganda effort, if you like, to explain to people that our values represented the best of commitments to individual dignity, to liberty and to human life being taken seriously. And I think that's what we are going to have to talk about in the next few years".