A  British parliamentary committee has launched an investigation into whether the country's intelligence chiefs committed an error by claiming that Saddam Hussein possessed weapons of mass destruction.

Also Read US intelligence about Iraq WMD 'faulty'

The investigation is being carried out by the Intelligence and Security Committee, on which the ruling Labour Party has a majority, and falls short of a full scale public inquiry demanded by opposition MPs.

The ISC is also not required to publish the results of its investigations. Nevertheless, the decision to hold the inquiry is a cause of concern to Prime Minister Tony Blair, who had hoped to draw a line over his decision to go to war.

Controversy about the war has been fuelled by the US administration which has now admitted that its own intelligence had been faulty.

US President George Bush's National Security Adviser Condoleezza Rice has conceded: "I think what we have is that there are differences between what we knew going in and what we have found on the ground."

Former US chief weapons inspector, David Kay, has also said he now believed Saddam told the truth when he said he had destroyed his weapons years ago.

Dr Kay said he believed Saddam destroyed his chemical and biological weapons in secret, but then tried to bluff the rest of the world into thinking he still had them.

"If the weapons programme existed on the scale we anticipated, we would have found something," he told the US media.  "Instead we have found evidence that points to something else."

Kay added that Saddam had practiced "creative ambiguity" by keeping his reduced capability a secret. "Saddam wanted to enjoy the benefits of having chemical and biological weapons without having to pay the costs," he explained.

Kay's views correspond to those of former UN weapons inspector Hans Blix - whose claims that Saddam probably destroyed his WMD arsenal 10 years ago were derided by the coalition.

The ISC will summon MI6 security service chief Sir Richard Dearlove and other intelligence agencies to justify their claims that Saddam had chemical and biological weapons at 45-minutes standby, was developing new ones and was trying to build a nuclear bomb.

The ISC has already published one report on the issue, which cleared Downing Street of deliberately "sexing up" the 2002 weapons dossier on Iraq.

A  former senior military intelligence official has accused the government of using the intelligence services in a "public relations exercise."

Air Marshal Sir John Walker said Lord Hutton's conclusion that Downing Street did not misrepresent intelligence meant the agencies themselves was liable to be questioned.. "If we take Hutton's results as read, we are left with an intelligence failure," Air Marshall Walker said.