'God will judge me on Iraq invasion' says Blair
In a rare departure from his usual reticence about discussing his faith in public, Mr Blair talks openly about his Christianity in a television interview to be broadcast on ITV tonight.
Amid continuing turmoil in Iraq - sectarian violence claimed another 25 lives yesterday - the veteran chat show host Michael Parkinson asks Mr Blair about the decision to invade Iraq.
More than 100 British troops have died there since the invasion three years ago. Many now fear the country is on the verge of full-blown civil war.
"That decision has to be taken and has to be lived with," the Prime Minister replies. "In the end there is a judgment that, well, I think if you have faith about these things, then you realise that judgment is made by other people... if you believe in God, it's made by God as well."
Asked if he prayed when making the decision, Mr Blair suggests that he did seek spiritual guidance.
"Well, I don't want to get into something like that," he says. "But of course you struggle with your conscience about it because people's lives are affected."
Since the invasion, Downing Street officials have been acutely sensitive about any link between Mr Blair's faith and the war. George Bush, the US president, last year faced derision after allegedly claiming God told him to topple Saddam Hussein.
When Mr Blair addressed Britain on the eve of war in March 2003, his aides forced him to drop plans to end his televised speech with the words "God bless you". Alastair Campbell, his communications chief at the time, also interrupted a magazine interviewer questioning the Prime Minister about religion, saying: "We don't do God."
But in tonight's interview, Mr Blair talks at length about his Christianity, confirming that his faith informs his politics.
"If you have a religious belief it does, but it's probably best not to take it too far," he says.
Mr Blair explains his interest in politics ultimately stems from his belief in God, a situation he says he first accepted while he was a student at Oxford University.
"I kind of got into religion and politics at the same time," he says. "I began to think about the world differently. And so I got interested in that at the same time as I became interested in politics."
In the interview, Mr Blair ducks most questions put to him about contemporary politics and his plans for life after Downing Street, but he tacitly admits to some friction with his presumed successor, the Chancellor, Gordon Brown.
"Politics is very hard to have a friendship in," Mr Blair says. "There is only one top job and it's not an ignoble ambition to want it, so there's all those difficulties there."
Last night, news of Mr Blair's comments provoked strong reactions. Rose Gentle, whose son Gordon was killed in Basra in 2004, said she was "quite disgusted" at the comments made by the Prime Minister.
The Military Families Against the War campaigner said: "How can he say he is a Christian? A Christian would never put people out there to be killed."