LONDON: Probes on both sides of the Atlantic into claims Washington and London hyped evidence of Iraq's weapons of mass destruction to justify war spell more political risks for British Prime Minister Tony Blair than his American ally George W. Bush.

As international cynicism mounts over the justification for war against Saddam Hussein, both the US Congress and the UK parliament are moving towards investigations into the validity of intelligence information about his weapons' threat.

The US Senate committees raking over the issue are more powerful than their UK equivalents. But Blair faces a more hostile public and legislature, making the threat to his credibility much greater, analysts and diplomats said.

"If weapons of mass destruction are not found - and that is still a big 'if' - and there is a feeling his government misled the people, then Tony Blair is in big trouble," said Vernon Bogdanor, an Oxford University professor of government.

"I think Bush is in a different position," he added, noting that the US pre-war emphasis on Saddam's weapons was less central than Britain's and that Americans were more likely to accept that it was a good thing anyway to get rid of Saddam.

Americans also focus more on the domestic economy now than lingering issues from a faraway war, diplomats added.

"The WMD issue has dogged prime minister Blair non-stop as he's gone around in the last week or so," said a diplomat close to both governments. "In the United States, it's not unimportant, it's on the radar screen, but it's not dogging US officials to the same degree as Blair."

Press scrutiny has reached fever-pitch in the UK - especially since a BBC report accusing Blair's office of making an intelligence report "sexier" by adding the line that Saddam could deploy weapons at 45 minutes' notice.

The British media also jumped on comments last week by US Deputy Defence Secretary Paul Wolfowitz that the US decision to stress the weapons' threat was taken for "bureaucratic" reasons, and by Defence Secretary Donald Rumsfeld that Iraq may have destroyed its WMDs before the war.

But those in Britain demanding a full public inquiry are sceptical the two parliamentary bodies investigating the matter - the Foreign Affairs Committee and the Intelligence and Security Committee - have sufficient clout.

The former can only make suggestions to parliament, where Blair has a large majority, while the latter reports to him.

"There is the embarrassment factor if the government were to refuse to co-operate with the committee," said foreign affairs committee chairman Donald Anderson. "But yes we are rather jealous of the powers of Congress."

Just the fact an inquiry is going ahead is a symbolic blow to Blair, and any finding that he doctored evidence to justify an unpopular war would be political dynamite, analysts said.

Potential damage to Blair also depends on the size of any revolt by sceptics within his ruling Labour Party and the impact on opinion polls. The latest survey found 43 per cent of Britons believe he distorted information.

By contrast, the US Senate bodies - the Senate Intelligence Committee and the Armed Services Committee - mulling a formal probe, have greater powers to demand witnesses and documents and are less bound by party loyalty.

US officials have rowed back on WMD in recent days, but the public mood appears more tolerant towards Bush.

Agencies via Xinhua