Tony Blair said today that moderate British Muslims were not doing enough to tackle the problem of extremism in their communities, which could not, he said, be defeated by the Government alone.

Speaking ahead of Friday's anniversary of the 7/7 London suicide bombings, the Prime Minister said that Muslim leaders should make clear to the extremists that not only were their methods wrong, but their ideology, interpretation of Islam and their "completely false sense of grievance against the West".

"I think the roots of this extremism lie in the attitudes and ideas as much as organisation," Mr Blair told the Commons Liaison Committee. "I don’t think there is an answer to this terrorism that is simply about police work or security measures."

Mr Blair spent some two hours answering questions from the Committee, which is made up of the senior MPs who head the various select committees. He also defended his Government's plans to reform the criminal justice system and said that energy security and climate change targets could not be met without a new generation of nuclear power stations.

His comments on the rise of Islamic extremism coincided with the publication of a Times poll showing that 13 per cent of British Muslims think that the the four London suicide bombers, who killed 52 people on three London Tube trains and a bus, should be regarded as "martyrs".

The Populus poll, for The Times and ITV News, nevertheless showed a stark gulf between those who considered that British Muslims were at war with the rest of society and the majority who want firm action against extremism. According to the survey, the largest poll of British Muslims ever undertaken, 56 per cent thought that the Government was not doing enough - against 49 per cent of the population as a whole.

Mr Blair was pressed by John Denham, chairman of the home affairs committee, who said that many who worked on the Government's post-7/7 Muslim working groups felt let down by a lack of follow-through - an accusation also raised by the prominent Muslim Labour MP Sadiq Khan.

Mr Blair said: "In the end, Government itself cannot go and root out the extremism in these communities. I am not the person to go into the Muslim community and explain to them that this extreme view is not the true face of Islam."

The Prime Minister went on: "I profoundly disagree that the problem here is that the Government hasn’t acted. We are not having a debate of a fundamental enough nature within the community, which is where the moderate majority go and stand up against the ideas of those people, not just their methods.

"You cannot defeat this extremism through what a Government does. You can only defeat it within a community. "People should stand up and not merely say, ‘You are wrong (but) you are wrong in your view about the West, you are wrong in your sense of grievance, the whole ideology is profoundly wrong’."

Mr Blair again ruled out an inquiry into the London Tube bombings, which he said would a waste of time and money and an irresponsible diversion of police efforts. "I believe at the moment we have a clear, active threat. I want our police and our security services focused on dealing with that threat," he said.

"My worry - and why I think it would not be responsible to do it - is that you end up diverting this vast amount of energy and resource into something that, I’m afraid in the end, is going to tell you what we already know, which is that these four individuals went and committed this act."

Mr Blair said he understood why people wanted an inquiry, in the face of continuing media reports that the security services had information which they failed to act upon - but he insisted that none of the stories was true.

"Each and every one of these stories is wrong and false," he said. "There was no CIA block on Mohammad Sidique Khan going into America, there was no device planted in his car before 7/7, there was no information given to the police before 7/7 about what they were up to. Each of these stories is just simply wrong."

Mr Blair also defended the recent police anti-terror raid on a home in Forest Gate in East London in which one man was shot, even though nothing was found at the address.

"I suspect actually that most Muslims would recognise that Forest Gate in a sense had to happen," he said. "The police, if they receive this information, what can they do? They are bound to go and investigate and take whatever action, and actually if they didn’t, most people would say they are not performing their duty properly."

He acknowledged, however, that it had created tensions which needed to be addressed."There is an issue between the West and the Muslim world and it does make these issues more difficult to resolve," he said. "There is no way round the situation in Forest Gate and we are going to have to work very, very hard to make sure the community understands why these things are done and the engagement between the police and community is an important part of that."

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