The charges of abuse against U.S. soldiers are reviving some Britons' discomfort over Blair's close ties to President Bush. British troops are also accused of mistreatment, and Blair's top ministers have admitted they waited three months read a Red Cross report on detention conditions.
Blair said Wednesday that alleged abuse of prisoners in Iraq "has been immensely damaging" but claimed all complaints about British troops had been addressed.
Over more than a year, Blair has encountered a series of episodes that threatened his premiership, most of them related to the Iraq war.
In his book Plan of Attack, Bob Woodward wrote that invading Iraq was so unpopular in Blair's Labor party that Mr. Bush was worried Blair's government would fall. In March 2003, Woodward says, Mr. Bush offered Blair a to the war.
Blair refused. Since then, a string of controversies has dogged the prime minister, from the failure to find weapons of mass destruction in Iraq, to a bitter dispute with the BBC over reports that the case for war was "sexed up" and even the suicide of a British weapons scientist.
Blair has also had sharp disagreements with many in the Labor party over domestic issues such as college fees and hospital funding.
So far, Blair has survived. But now, the left-leaning Guardian newspaper reported Wednesday, "normally loyal (members of parliament) believe (Blair's) fate may be spiraling beyond his control."
One loyalist told the Guardian: "This is a complete disaster. Are we going to reach a point where people think we are not fit to govern?"
The newspaper reported earlier in the week that Blair had told associates he would stand aside if he became a liability to his party in elections expected next summer.
Blair's survival to date might be chalked up to the same reason he became Labor leader, despite having centrist views at odds with Labor party dogma: He can win. In 1997, Blair was able to return the Labor party to power after 18 years of Conservative rule, and he won a resounding re-election victory in 2001.
But now that another election is approaching, Blair's position may parallel that of former Prime Minister Margaret Thatcher. In the 1970s and 1980s Thatcher energized the Conservative party, but eventually her popularity sagged. She was ousted as leader in 1990, allowing John Major to win another term for the Tories in 1992.
Blair's personal popularity is important not just to Labor but also to the success of a planned . Blair is pushing for a "yes" vote to complete his long push for better integration with the mainland; polls show a tight race.
Blair, speaking in the House of Commons on Wednesday, avoided comment on allegations of abuse by U.S. forces, while saying: "I agree that the events of the past few days have been immensely damaging."
He also said that photos of British troops allegedly abusing an Iraqi prisoner, published by the Daily Mirror newspaper, "were almost certainly fake." The newspaper has not withdrawn its report.
An Amnesty International released Tuesday listed only one case of a civilian death which was not already known to the government, Blair said.
"Any abuse by any coalition forces is completely unacceptable," Blair said. "What is not true is that allegations were made and nothing happened in respect of them."
Conservative Party leader Michael Howard tried to press Blair about why no government minister seemed to be aware of the Red Cross report detailing abuse of prisoners until this week. Defense Secretary Geoff Hoon and Foreign Secretary Jack Straw said they had not previously seen the report, though Straw said Tuesday it would have been better if he had.
"How can the people of this country have confidence in this prime minister and his government?" Howard said.
Blair accused Howard of attempting to "extract the maximum political mischief" from the controversy, but did not explain why the report reached senior ministers only this month.
He repeatedly said that British authorities were dealing with each of the abuses cited by the Red Cross. In one instance — the hooding of prisoners — the practice was stopped months before the Red Cross report, Blair said.
Earlier, former Archbishop of Canterbury George Carey said alleged torture and abuse of Iraqi prisoners by British and America troops condemns the whole of the West in the eyes of the Arab world.
"It is deeply shameful and it indicts us all in the West. It is cruel, it is horrible, it is degrading," Lord Carey said in an interview with British Broadcasting Corp. radio.
"I don't know how we can pull out of this. Apologies are not enough," said Carey, who retired as archbishop in 2002.