And one theory is that by leaving now, he has attempted to avoid the opprobrium of departing as a guilty man.Mr Campbell had assured the inquiry that he had "no input, output, no involvement" whatsoever in drawing up last September's Iraq weapons dossier. Similarly, he insisted that he played no part in disclosing the identity of Dr David Kelly, the source of the BBC journalist Andrew Gilligan's report about the Government "sexing up" the dossier, to the media.It took little time for Mr Campbell's defence to unravel. Official papers posted on the Hutton inquiry website showed that he had asked John Scarlett, chairman of the Joint Intelligence Committee (JIC), in charge of compiling the dossier, for no less than 15 changes to the draft dossier a week before its publication on 24 September. This included one affecting the claim that Saddam Hussein could launch a chemical and biological attack within 45 minutes.The Hutton documents show that Mr Campbell may have misled Parliament as well as the inquiry. After giving his testimony to the Commons Foreign Affairs Select Committee examining the Government's case for war, in June, Mr Campbell admitted asking Mr Scarlett for 11 changes. The letter, leaked to a national newspaper by a Labour MP on the committee, showed that Mr Campbell had not referred to the "45 minutes" threat. Lord Hutton, however, published the original letter Mr Campbell sent to the JIC chairman.

It showed that he had, in fact, asked for changes to the supposed "45 minutes threat", and obtained his demand. The draft dossier had stated that Iraq "may be able to deploy chemical or biological weapons within 45 minutes". Mr Campbell complained in his letter that the word "may" was too weak Mr Scarlett replied that "the language you queried .. had been tightened". The published dossier read: "The Iraqi military are able to deploy these weapons within 45 minutes of a decision to do so."The Hutton documents also revealed that Mr Campbell had prevailed upon the JIC chairman to include a claim in the dossier that Saddam could have a nuclear arsenal within two years.Mr Scarlett's draft dossier had said that on the eventuality of the United Nations sanctions being lifted Iraq would take five years to produce a weapon but that "this timescale would shorten if Iraq succeeded in obtaining fissile material from abroad".On 18 September Mr Campbell wrote to Mr Scarlett in an e-mail that he had shown the draft dossier to a woman in his office who found the nuclear section "confusing and unconvincing". During his evidence, pointing the finger of responsibility firmly at Downing Street, the Defence Secretary told the inquiry how Mr Campbell had told him that he wanted to leak Dr Kelly's name to a "friendly" newspaper.

Mr Smith, one of the Prime Minister's official spokesmen, told Lord Hutton that he had overheard the conversation. He expressed his reservations to Tom Kelly, Mr Blair's other spokesman, and together they managed to dissuade Mr Campbell from his plan.. As tributes were paid by his political friends last night, Alastair Campbell's foes accused him of staging a final act of spin designed to deflect attention from the Hutton inquiry. The Prime Minster said: "The picture of Alastair Campbell painted by parts of the media has always been a caricature."The Alastair Campbell I know is an immensely able, fearless, loyal servant of the cause he believes in, who was dedicated not only to that cause but to his country."He is a strong character who can make enemies but those who know him best, like him best. His contribution to the Labour Party's modernisation, and electoral success, was enormous."He was joined by high ranking Labour politicians past and present. David Blunkett, the The Home Secretary, said: "Alastair has often been controversial and occasionally infuriating, but has always been the most effective, talented and committed spokesman for the Prime Minister, Government and party that any prime minister has ever had."The former Labour leader Neil Kinnock described him as a "loyal, brave and audacious man". And even though Mr Campbell was often described as the "real" deputy prime minister, John Prescott - who actually has the job title - declared yesterday "a sad day.

I'm grateful for [his] contribution to the Labour government," he said.Robin Cook, the former foreign secretary, who was said to have been advised by Mr Campbell after news of his marital infidelity broke, said: "I have a lot of respect for Alastair He has been a great asset to Labour. I always found Alastair straight and was always glad when I took his advice. He deserves to be remembered for his contribution over a whole decade in giving the best possible presentation to our message, in opposition and in government."Lord Guthrie, a former chief of the defence staff, said: "I never found him anything but helpful, someone who gave good advice and understood the problems of the services. I speak as a cross-bencher with no political affiliation, but as someone who got to know Alastair very well during a number of international crises, notably the conflict in Kosovo."James Rubin, a former US assistant secretary of state, worked with Mr Campbell during the Clinton presidency. He described him as "always steadfast, working at the highest possible distinction".But others were more sceptical.