Powell withdraws al-Qa'ida claim as hunt for Saddam's WMD flags

The faltering American and British case for war in Iraq has suffered another blow with an admission by the US Secretary of State, Colin Powell, that there was no hard proof of links between Saddam Hussein and al-Qa'ida, contrary to his claims before the invasion.

"I have not seen smoking-gun, concrete evidence about the connection," Mr Powell said last week. Almost at the same moment, the assertion that Iraq had weapons of mass destruction - another crucial aspect of the Secretary of State's presentation to the UN Security Council last February - was being further discredited.

Not only did it emerge that a 400-member military team tasked with searching for unconventional weapons in Iraq had been quietly withdrawn, a leading Washington think tank, the Carnegie Endowment for International Peace, accused the Bush administration of "systematically misrepresenting" the danger of Saddam's alleged WMD before the war. The Washington Post also reported the discovery of a document suggesting Iraq might have destroyed its biological weapons more than a decade ago, and that subsequent "programmes" existed only on paper.

Mr Powell defended his pre-war statements on Iraq and al-Qa'ida, saying: "I think the possibility of such connections did exist, and it was prudent to consider them at the time that we did." Top administration officials also contend that the WMD hunt is not over, despite indications that scarcely any effort is being made on the ground.

In charge is the 1,400-member Iraq Survey Group - a number itself inflated by the inclusion of Iraqi drivers, translators and other support staff. But the ISG has been severely depleted by the withdrawal of intelligence personnel to deal with a higher priority: the insurgency that is killing large numbers of occupation troops. Its head, David Kay, a hawk who confidently predicted the discovery of WMD, has given notice of his resignation to the Bush administration.

Last week, The New York Times reported that a military team specialising in the disposal of chemical and biological weapons remains part of the ISG in Iraq, but is "still waiting for something to dispose of". Important evidence might be contained in a vast collection of seized Iraqi documents being stored in a secret military warehouse in Qatar, say American officials, but only a small fraction had been translated.

Evidence that the search for WMD has been all but abandoned, and increasingly frank admissions in Washington that the threat from Saddam's regime was exaggerated in the run-up to war, have scarcely dented the Bush administration's popularity. But while the White House can say that WMD was never the main reason it sought "regime change" in Iraq, the danger of Saddam's alleged weapons was central to Tony Blair's case for war, both legally and politically.

The Hutton inquiry into the death of the weapons scientist David Kelly heard much testimony on the question of whether intelligence on Iraqi WMD was distorted. As the Prime Minister awaits Lord Hutton's findings, the failure to find any sign of illegal weapons programmes in Iraq, let alone the weapons themselves, is highly damaging.

As recently as his Christmas message to troops in Iraq, Mr Blair said weapons hunters had unearthed "massive evidence of a huge system of clandestine laboratories" in Iraq, only for the claim to be dismissed by Paul Bremer, America's most senior official in Baghdad, before he knew who had made it.

Significantly, the Prime Minister made no mention of WMD during his lightning visit to Iraq last weekend, instead stressing the role of British forces in bringing stability to the country.

The Carnegie Endowment report, compiled over six months, is scathing about the deliberate errors and omissions of the White House - and, by extension, Downing Street - saying the thesis that Iraq or another rogue state would make WMD available to terrorists was "questionable" and "unexamined".

Officials ignored caveats by the intelligence agencies, and consistently adopted "worst case" assumptions.