HOWZAT

He also noted that the search for banned weapons continued, adding: "we need more time … While many of us want instant answers, the search for biological weapons in Iraq will take time and will take patience."

Mr Tenet said that intelligence on Iraq was gathered by agents, satellites and telephone interception. Analysts also looked at Iraq's history and Saddam's willingness to use chemical or biological weapons against his own people.

Mr Tenet went on: "In the intelligence business you are never completely right or completely wrong." He said it was important that there was not "politicised, haphazard evaluation" of intelligence.

He said it was vital that intelligence analysts were not discouraged from reaching conclusions, which were sometimes inevitably wrong. Such an environment would lead to "an intelligence community that is damaged and a country that is more at risk".

He denied claims that analysts had been ordered by politicians to reach conclusions about Iraq in the October 2002 National Intelligence Estimate. "No one told us what to say or how to say it," he said.

Analysts "painted an objective assessment for our policy makers of a brutal dictator who was continuing his efforts to deceive and build programmes that might constantly surprise us and threaten our interests", he said.

Donald Rumsfeld, the US Defence Secretary, defended intelligence work at a Senate hearing yesterday, saying: "The reality is we have had some wonderful successes, and some of them not public. The failures are very visible, and that's always the case."

Mr Tenet's speech came after the former top US weapons inspector in Iraq said that intelligence agencies were "wrong" about Iraq's weapons of mass destruction.

David Kay, who led the Iraq Survey Group until last month, said that he believed there were no stockpiles of such weapons hidden in Iraq. Dr Kay told the Senate Armed Services Committee that intelligence failures were to blame for the conclusion that there would be WMD stockpiles.

"It turns out we were all wrong, probably in my judgment, and that's most disturbing," he said.

He added that an independent inquiry was necessary, "not only for what happened in the past but so we can reply on any intelligence in the future". Dr Kay said that much evidence about Iraq's WMD was lost in the orchestrated looting which followed the capture of Baghdad by American troops. Mr Tenet agreed with that analysis.

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