Mr Tenet says he almost refused a presidential award in 2004

In a new book, Mr Tenet accuses the US administration of failing to properly debate the evidence for going to war.

And he said one of his own comments was distorted by the US vice-president.

Mr Tenet, who resigned in 2004, is the first member of President Bush's inner circle to pen a memoir recalling 9/11 and the wars in Afghanistan and Iraq.

His 549-page book, At The Centre of the Storm, focuses on Mr Tenet's seven-year tenure as CIA director.

There was never a serious debate that I know of within the administration about the imminence of the Iraqi threat

George Tenet

Former CIA director

"In retrospect, we got it wrong partly because the truth was so implausible," he writes.

Speech dropped

But Mr Tenet is unequivocal in his judgement about the administration's approach to Iraq before 2003.

"There was never a serious debate that I know of within the administration about the imminence of the Iraqi threat," he writes.

Special criticism is reserved for the US Vice-President Dick Cheney, who he says had to be reined back on one occasion from delivering a speech that explicitly linked Saddam Hussein to al-Qaeda.

Mr Tenet also accuses the vice-president of twisting the meaning of one of his own remarks.

In the months preceding the invasion, Mr Tenet told a high-level meeting that conclusive evidence that Iraq possessed weapons of mass destruction (WMD) would be a "slam dunk" in publicly promoting the case for war.

Mr Tenet insists that his remark was theoretical and was not intended to persuade President Bush that Iraq actually had WMD.

Mr Cheney has since told a TV interviewer that the "slam dunk" remark helped convince Mr Bush to give the go-ahead for war - an argument Mr Tenet laughs off in his memoir.

"I remember watching and thinking: 'As if you needed me to say "slam dunk" to convince you to go to war with Iraq,'" he says.