Anti-war protesters have staged a demonstration outside Westminster Cathedral while Tony Blair was making a speech about religion.

Stop The War Coalition (STWC) protesters tried to drown out the former prime minister by blowing whistles, beating drums and banging pots and pans together.

Mr Blair's conversion to Catholicism after leaving Downing Street last year angered opponents of the invasion of Iraq, who have accused him of hypocrisy.

Lindsey German from the STWC said: "If Tony Blair wants a public platform, it should be from the dock at the the International Criminal Court at The Hague."

There was a silent protest against Mr Blair's visit by Pax Christi UK, a Catholic peace organisation.

Taking part in the vigil was Norman Kember, the British peace activist held hostage in Iraq at the end of 2005.

He said: "What happened to me was a minor blip in my life compared to the continuing plight of Iraq and the way ordinary Iraqi citizens have suffered so much.

"I feel it is partly Mr Blair's fault and I don't like the idea of him talking in a church."

In his address Mr Blair warned that religion should be reclaimed from extremists and "awaken the world's conscience".

He said: "In the last 10 years we have also been reminded sharply, in acts of terror committed in the name of faith, that we ignore the power of religion at our peril."

"Religious faith is most obviously associated with extremism in the name of Islam through the activities of Al-Qaeda and others.

"Even if by far most religious people are not prone to the use of terror, at least not nowadays, there are extremists in virtually every religion."

Mr Blair, who said he was "not a religious leader" and made "no claims to moral superiority" is currently working as an international envoy to the Middle East.

He set out plans for the Tony Blair Faith Foundation, to be launched later this year, which aims to bring different faiths together to promote education and combat poverty, hunger and AIDS.

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