WASHINGTON, Sept 28: The intelligence committee of the US Congress has said that American intelligence agencies used largely “outdated, circumstantial and fragmentary” information to back Washington’s claim that Iraq had weapons of mass destruction and links with Al Qaeda.

The information had with “too many uncertainties,” says a Congressional report, which appeared in The Washington Post on Sunday.

The report was prepared by the House Permanent Select Committee on Intelligence, which spent four months combing through 19 volumes of classified material used by the Bush administration to make its case for the war on Iraq.

The committee found “significant deficiencies” in the ability of the US intelligence agencies to collect fresh intelligence on Iraq. The report pointed out that often the agencies had to rely on “past assessments” dating to when UN inspectors left Iraq in 1998 and on “some new piecemeal intelligence,” both of which “were not challenged as a routine matter.”

“The absence of proof that chemical and biological weapons and their related development programmes had been destroyed was considered proof that they continued to exist,” said a letter two committee members sent to CIA Director George J. Tenet on Thursday, a copy of which was obtained by The Washington Post this weekend.

“The letter constitutes a significant criticism of the US intelligence community from a source that does not take such matters lightly,” the Post observed.

The committee, like all congressional panels, is controlled by Republicans, and its chairman, Rep. Porter J. Goss, is a former CIA agent and a longtime supporter of Mr Tenet and the intelligence agencies. Mr Goss and the committee’s ranking Democrat, Rep. Jane Harman, signed the letter.

CIA spokesman Bill Harlow said the agency could not comment because it has not had a chance to review the letter.

The letter said the buildup to the war in Iraq amounted to “a case study” of the CIA’s and other agencies’ inability to gather credible intelligence from informants in Iraq or to employ technologies designed to detect weapons programmes.

“Lack of specific intelligence on regime plans and intentions, WMD, and Iraq’s support to terrorist groups appears to have hampered the intelligence community’s ability to provide a better assessment to policymakers from 1998 through 2003,” the letter said.

On the question of Iraq’s ties to terrorists, the committee scrutinized three volumes of data and found that “substantial gaps” in credible information from human sources that would have allowed US intelligence agencies “to give policymakers a clear understanding of the nature of the relationship.” Instead, the agencies had a “low threshold” or “no threshold” on using information the intelligence community obtained on Iraq’s alleged ties to Al Qaeda.

“As a result, intelligence reports that might have been screened out by a more rigorous vetting process made their way to the analysts’ desks, providing ample room for vagary to intrude,” the letter states. The agencies did not clarify which of their reports “were from sources that were credible and which were from sources that would otherwise be dismissed in the absence of any other corroborating intelligence.”

The letter is particularly critical of the underlying intelligence used to conclude that Iraq was reconstituting its nuclear programme.

“Our examination has identified the relatively fragile nature of this information,” the letter states. It notes internal intelligence agency disputes about whether Iraq attempted to buy high-strength aluminium tubes that could be used in nuclear weapons manufacture, and points out the dual-use nature of other attempted purchases of equipment cited in US intelligence reports.

The letter dispels the assertion, made frequently by the administration officials, that they possess more concrete information about Iraq’s nuclear intention, but are unable to disclose it because it remains classified. “We have not found any information in the assessments that are still classified that was any more definitive,” the two wrote.