Publication of a secret 2003 memo from Britain's top government lawyer questioning the Iraq war's legality buffeted Prime Minister Tony Blair today, just a week before the May 5 election.
Trailing in opinion polls, opposition parties pounced on the report from Attorney General Lord Peter Goldsmith as showing Blair had deceived Britain.
"If you can't trust Mr Blair on the decision to take the country to war, the most important decision a prime minister can take, how can you trust Mr Blair on anything else ever again," asked opposition Conservative leader Michael Howard.
Mr Blair, confident Labour's strong economic record will win him a third term, called the affair "a damp squib".
Having refused past demands to release the memo, Mr Blair authorised full publication today to try and defuse the row after excerpts were leaked to British media.
The deeply unpopular Iraq war remains Mr Blair's Achilles Heel, enabling foes to attack him on trust and integrity.
Today's cacophony of claims that Mr Blair leant on Mr Goldsmith to swallow his doubts echoed accusations the government also pressured intelligence services to hype evidence of Saddam Hussein's banned arms before the 2003 US-led invasion.
The Goldsmith leak has ruined Mr Blair's efforts to focus the campaign run-in on domestic issues like the economy and health.
But analysts said it was unlikely to sway many voters at this late stage. "They don't trust Mr Blair to tell the truth, but they have long ago made up their minds about that and there is no reason to think that they would trust the Conservatives any more," political analyst Anthony King said.
The March 7, 2003 document creating all the furore shows that Mr Goldsmith cast doubt on the legal grounds of war just days before Mr Blair ordered troops in.
Mr Goldsmith said then "a court might well conclude" UN Security Council resolutions at the time did not authorise war and that "the safest legal course" was a fresh UN motion.
But he was not categorical, also saying Britain could build "a reasonable case" for war based on two earlier UN resolutions if it had "hard evidence" of wrongdoing by Saddam.
Ten days later, when Britain had failed to get a new resolution, Mr Goldsmith gave the cabinet and parliament short written advice that war was legal, and mentioned no doubts.