Liberal Democrat leader Charles Kennedy raised the spectre of future military action against Iran yesterday as he demanded a public inquiry into the war in Iraq and the conduct of Tony Blair and his ministers.
And he forced the Blair/Bush axis centre-stage in the campaign, as he declared: "Iraq does deserve to be a central issue in this election, not only because of what has happened, but because of what may yet come to pass."
As Conservative leader Michael Howard again accused the prime minister of lying about the war, Mr Blair called for an end to personal attacks on his "character and integrity", while defiantly asserting he had been right to remove Saddam Hussein.
However, the intriguing and complex pitch to Labour voters disillusioned by the war was dramatically revealed when London mayor Ken Livingstone intervened on Mr Blair's behalf in a growing debate which the Lib Dems clearly believe could yet affect the election outcome.
Acquitting Mr Blair of the charge of lying, Mr Livingstone insisted the election was not "a referendum" on the conflict but rather about the election of a government and the future expansion of Britain's public services.
However, the mayor also said "the war was wrong" and "driven primarily by America's oil interests". He then reassured Labour opponents of the war that no Labour prime minister could ever again support "an American adventure" and suggested that "the peace camp has won the war".
With his attempt to resume campaigning on the economy overshadowed by the Lib Dem and Conservative assault, Mr Blair defended his decision to go to war.
"I can't say I am sorry about it. I am not sorry about it. I think I did the right thing," he said.
And while he had "no disrespect" for those who had disagreed with him, Mr Blair accused the Conservatives of mounting "a full-scale assault on my character" because they had nothing else to offer.
"I have no disrespect for people who disagreed with me over Iraq," said Mr Blair.
"I simply ask them to conduct the debate on the terms of whether the judgment was right or not."
However, Mr Kennedy said the war had undermined the United Nations and international law, as well as Mr Blair's "own standing" and that of his government and politics generally.
And he insisted there was insufficient basis to trust Mr Blair's word about possible future military actions.
Mr Kennedy said some analysts were predicting a strike against Iran within 18 months, and that foreign secretary Jack Straw had been "commendably unequivocal in his insistence that such action would be inconceivable". However, he continued: "Tony Blair as prime minister, by contrast, has only gone so far as to say there are no plans for an attack on Iran. The problem the prime minister has is that we do not have sufficient reason to trust his word when it comes to that issue."
The Lib Dem leader suggested Mr Blair would see an election victory as providing the "green light" for military strikes in Iran.
Calling again for publication of the attorney general's full written advice on the legality of the Iraq war, Mr Kennedy said every Labour and Conservative candidate who supported it should be held to account by voters.
As Mr Kennedy went on the anti-war offensive, his party placed advertisements in yesterday's Daily Mail and Daily Mirror underlining its opposition to the position of Mr Blair and President Bush.
Under a smiling photograph of the two leaders, the Lib Dems declared: "We oppose: Bush and Blair on Iraq. We propose: never again."
With the launch of his party's business manifesto also over-shadowed by the row, Mr Howard was pressed about his claim that Mr Blair had lied. But an unrepentant Mr Howard replied: "I'm afraid I tell it as it is and I tell it as I find it, because this election is about trust."