Tony Blair has admitted for the first time that he ignored the pleas of his aides and ministers to deter President Bush from waging war on Iraq because he believed that America was doing the right thing. And he has acknowledged that he turned down a last-ditch offer from Mr Bush to pull Britain out of the conflict.

He has also revealed that he wishes he had published the full reports from the Joint Intelligence Committee (JIC) instead of the infamous September dossier about Saddam Hussein’s alleged weapons of mass destruction that so damaged him, and was almost certainly one of the factors that contributed to him leaving office sooner than he wanted.

In frank remarks in a BBC documentary, Mr Blair confirmed openly the belief of many of his closest supporters that he never used his position as America’s strongest ally to try to force Mr Bush down the diplomatic rather than the military route.

It was never a “bargaining chip” for him and he was never looking for a way out, he told David Aaronovitch, of The Times, in interviews for The Blair Years. “It was what I believed in, and I still do believe it,” he said.

The documentary contains clear evidence that many of those around Mr Blair, including Sir David Manning, his foreign policy adviser, Jeremy Greenstock, Britain’s ambassador at the UN, Jack Straw, the Foreign Secretary at the time, and even Colin Powell, the US Secretary of State, had huge reservations about the rush to war.Mr Blair said: “In my view, if it wasn’t clear that the whole nature of the way Saddam was dealing with this issue had changed, I was in favour of military action.”

The programme reveals that the key meeting at which Mr Bush learnt that he had Mr Blair on side took place at Camp David in September 2002 – six months before hostilities began. In return for promising Mr Blair that he would try to help get a second resolution at the UN, he also won Mr Blair’s pledge that if he got “stuck” in the UN, war would be the only way out. Mr Blair later suggested that Mr Bush tried for a second resolution as a “favour” to him.

The programme also reveals that just before the key Commons vote on war Mr Bush telephoned Mr Blair and offered him a way out. Mr Blair explained why he had declined the offer: “He was always very cognisant of the difficulty I had. He was determined we should not end up with the regime change being in Britain and he was saying to me, ‘Look I understand this is very difficult and America can do this militarily on its own and if you want to stick out of it, stick out of it’, and I was equally emphatic we should not do that.”

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