Responding to Tony Blair’s announcement yesterday that he will stand down as UK Prime Minister from 27 June 2007, the Archbishop of Canterbury Dr Rowan Williams praised his commitment to a plural society – while noting deep moral divisions over the Iraq war.

Speaking from Sri Lanka, where he is on a church visit, the Anglican leaders declared: “Tony Blair has understood as well as any Prime Minister in recent times why religion matters, how faith communities contribute to the common good and why religious extremism should have no place in a progressive society.”

He continued: “As a man of genuine personal faith, he has not shied away from the risk associated with confronting extremism, while respecting difference.”

Referring to the growth of what he sees as a narrow-agenda form of secularism, Dr Williams went on: “The Church of England, in common with all people of faith, is grateful that over the past ten years the Prime Minister has refused the demands of some to close down the space in our society within which both vigorous debate and the full diversity of religious conviction can find voice and be expressed.”

Others will argue that bishops in an unelected House of Lords and religious selection in publicly-funded schools are not so much spaces of open debate but archaic privileges which narrow participation.

The Archbishop’s comments about the most controversial aspect of Mr Blair’s premiership will also be perceived by some of their respective critics as excessively mild.

He said: “There have naturally been differences of vision and judgement between the Prime Minister and the Church of England, not least over the Iraq war, but he has been consistently willing to allow these disagreements to be voiced and discussed openly.”

Opponents of the war say that the PM is culpable for policies that have resulted in hundreds of thousands of dead, millions displaced, and a massive resurgence of terrorism.

Defenders say that the removal of Saddam Hussein was a moral act, although not the pretext for the 2003 invasion – in which Britain was the USA’s most solid ally, in spite of huge domestic opposition.

Dr Williams, who was critical of the war, has admitted that he should have acted more on the words of US church leaders who lobbied him and went to see Mr Blair before the invasion.

On brighter matters, Archbishop Williams praised the PM on what is widely recognised as his greatest success.

He said: “The current development in Northern Ireland bears witness to one of his most enduring achievements and the high profile given to development issues, especially in Africa, and to the environmental crisis reflects the passion and intelligence he has brought to his work as Prime Minister.”

Dr Williams concluded: “I wish the Prime Minister well in the future, whatever that holds for him, and I hope and pray that his recognition of the contribution of faith and faith communities to the common good of our society will prove to be one of his most enduring legacies; one that will be built on by his successors.”