Key points from Alastair Campbell's evidence to the House of Commons Foreign Affairs Select Committee.
Foreign Affairs Committee chairman Donald Anderson opens the hearing at 1502 BST.
Mr Anderson welcomes Mr Campbell to what some might see as the "lions den", or "Campbell in the soup".Mr Anderson said the committee's remit was very serious, stressing that the charge against Mr Campbell was whether, in his zeal to make the case for going to war, he embellished the evidence to mislead Parliament and the public at a vital time of peace and war.
Mr Anderson asked Mr Campbell if there was anything he regretted.
Mr Campbell, referring to February's "dodgy dossier", said: "I regret the fact a mistake was made in the drafting process."
Mr Campbell said the mistake in the February document was to incorporate parts of a student's thesis into it without attributing it - this meant that it was assumed the draft was all government material and thus altered.
Mr Campbell said the day after the mistake was revealed on Channel 4 and on BBC's Newsnight, he spoke to the security intelligence coordinator, the head of the intelligence service and others "to explain that something had gone wrong".
Mr Campbell said he was happy to say to Ibrahim al-Marashi, whose thesis was plagiarised in the February dossier, that his work should not have been used, adding: "I apologise for that."
Mr Campbell said the scale, breadth and impact of the September dossier and February's "dodgy dossier" was different.
The September dossier was "one of the most important pieces of work" that had been developed during the run up to the Iraq conflict, said Mr Campbell.
Mr Campbell said he regretted publishing the February paper, saying it was "not nearly as significant" as the dossier published in September 2002.
Mr Campbell said new procedures have since been put in place about how intelligence is handled when it is being put in the public domain.
Mr Campbell said he had never heard of Dr al-Marashi until the mistake in the February briefing paper was revealed by Channel 4 and BBC's Newsnight.
As a result of the mistake, Downing Street has agreed new procedures so that anything with an intelligence impact has to be cleared by the chairman of the Joint Intelligence Committee before it is published, said Mr Campbell.
Mr Campbell said he had not felt the February document should have been sent as a matter of routine to the Cabinet Secretary.
Mr Campbell said he had explained to the prime minister the purpose of the February briefing paper was to give to six Sunday newspaper journalists on a flight to Washington, that it contained new intelligence and information about Saddam Hussein's regime.
Tory committee member Sir John Stanley said Mr Campbell had been guilty of a grave failure in his briefing of the prime minister about the February document, which had been presented as having Joint Intelligence Committee status, when it was actually "largely culled off the internet".
Mr Campbell said the February document was a briefing paper produced by the Iraq Communications Group, a group which he chaired.
Mr Campbell insisted that the prime minister did not say the February document came with the "Joint Intelligence Committee seal of approval".
Mr Campbell said the prime minister was content with the paper as it was, but was not content with the fact that in its production there was a mistake, for which there has since been an apology.
Mr Campbell said the September 2002 dossier was hugely important and "was a huge break of precedent, with the intelligence agencies sharing so much information like that with Parliament and the public".
Mr Campbell said he had a "sinking feeling" about the February document on the way back from an interview the prime minister had had with BBC's Jeremy Paxman, when Channel 4 had made a reference to the story and it had been mentioned on Newsnight.
Mr Campbell said it "didn't take us that long to establish" the mistake made in the February document.
Mr Campbell said there were four meetings held in relation to the February document.
Referring to the September dossier, Mr Campbell said he queried some of its contents, including mention of Saddam Hussein's earnings of £3bn and vivid and graphic descriptions of his regime.
Mr Campbell said the reference to weapons of mass destruction being ready for launch within 45 minutes was contained in the first draft of the September 2002 dossier, put forward by the chairman of the Joint Intelligence Committee.
Mr Campbell said he did not think it was his place "to say hold on, what's this about?"
It was completely and totally untrue that he sought to exaggerate that intelligence or use it in anyway that the intelligence community was not happy with, said Mr Campbell.
Referring to allegations made by the BBC, Mr Campbell said: "They are basically saying that the prime minister had taken the country into a military conflict, and all that entails ... on the basis of a lie - that's a very, very serious allegation."
Mr Campbell said that allegation had been denied by the prime minister, the chairman of the Joint Intelligence Committee, the security and intelligence co-ordinator and others.
"I know that we were right in relation to that 45 minute point," insisted Mr Campbell.
Mr Campbell said Downing Street had apologised to Dr al-Marashi about the use of his thesis in the February dossier. "I think it's about time the BBC apologise to us in relation to that 45 minutes."
Labour committee member Greg Pope said BBC correspondent Andrew Gilligan had claimed Mr Campbell had "transformed" the original September 2002 dossier.
Mr Campbell denied that he had "sexed up" the dossier, had put pressure on the intelligence services and had made the 45 minute point more prominent.
Mr Campbell said he felt very strongly about the fact the prime minister, foreign secretary, chairman of the Joint Intelligence Committee and others had said it was not true that the 45 minute point had been made more prominent.
Mr Campbell said it was not right that the BBC's defence correspondent Andrew Gilligan was basing his claims on a single unnamed source.
Mr Campbell said he "did not accept the picture as it was portrayed" by Clare Short, the former international development secretary, who said the public were mislead.
Mr Campbell said "an official" had absorbed parts of Dr al-Marashi's thesis into the February document.
Of the February document, Mr Campbell said: "I certainly accept that it was a mistake", but whether it was a "complete Horlicks", as described by Foreign Secretary Jack Straw, he said it was more like a "storm in a tea cup".
Subject to the approval of the Joint Intelligence Committee, Mr Campbell said he had "no difficulty" in producing the changes that he had proposed to the September dossier on behalf of the prime minister.
Mr Campbell said he was not aware of anyone in the intelligence agencies who was unhappy with the production of the September dossier.
Mr Campbell said he had no doubt there would have been a debate within the intelligence community about the September dossier and its unprecedented contents.
But no reservations were expressed to the prime minister, or to him, by the chairman of the Joint Intelligence Committee or the heads of the intelligence service, said Mr Campbell.
Once the decision was taken for the September dossier to be primarily an intelligence based document, the chairman of the Joint Intelligence Committee took responsibility for it, said Mr Campbell.
Mr Campbell said the chairman of the Joint Intelligence Committee was assiduous in spotting potential inconsistencies in the dossier.
Mr Campbell said the September dossier was not designed to make the case for war - it was there to set out why the British government was so concerned to address the issue.
Mr Campbell said policy decisions were taken by the Cabinet, headed by the prime minister, but he "was involved in a lot of the decisions about policy and strategy on Iraq". "I'm there as an advisor to the prime minister," he said.
Mr Campbell said he did not recognise the characterisation of the prime minister as somebody who has taken a prior decision to take the country to war along with US President George Bush.
Mr Campbell said Mr Blair always agonised over sending British troops into conflict and possibly death.
The idea that you do that glibly or that you try and sex up a dossier as a way of trying to persuade the public that we should do it ... I know scepticism is fine ... but are we really so cynical that we think the prime minister, any prime minister, is going to make prior decisions to send British forces into conflict and wouldn't rather avoid doing that."
"I saw somebody working round the clock, flat out, trying to get this thing on the UN route," said Mr Campbell.
Mr Campbell said, in reference to the February document: "I never envisaged this being a significant thing."
"It was never meant to be a huge deal," said Mr Campbell, who said he thought journalists would find the February document "interesting", but "it wasn't making the case for war".
"It was intended to generate some media discussion and debate about this issue: Why was it so hard for the UN weapons inspectors to do their job?" said Mr Campbell.
Mr Campbell said he had to take "some responsibility" for the document getting into US Secretary of State Colin Powell's hands. Mr Campbell admitted giving a copy of the paper "to my opposite number" in the US.
Mr Campbell said Andrew Gilligan had talked about "his weird and wonderful meetings with his source".
Mr Campbell said he did not know who Andrew Gilligan's source was or how senior they were. But Mr Campbell said he personally had dealt with people in the intelligence services, over some years and in conflicts such as Kosovo and Iraq, "of the highest professionalism and in many instances, the highest bravery".
Mr Campbell said he could not think of a more serious allegation than "to say on the BBC that I was involved in conniving with the intelligence agencies to do this".
Mr Campbell said the BBC "will not admit they get things wrong".
Mr Campbell said the BBC story "says the prime minister, foreign secretary, with the connivance of me and the intelligence agencies persuaded Parliament and the country to go to war on a false basis". "I think that is a pretty unbelievable allegation to make unless it is sustainable."
"If that is BBC journalism, then, you know, God help them," said Mr Campbell.
"The prime minister said publicly that one of the reasons he wanted to do this was because there was continuing new intelligence he was seeing that made him feel that there was a growing threat from Iraq's weapons of mass destruction," said Mr Campbell.
Mr Campbell said the changes made to the September dossier had nothing to do with over-riding intelligence assessments, adding that the Joint Intelligence Committee chairman stood by every word in the document.
Mr Campbell said the first draft of the September dossier was "a very good and thorough piece of work".
Tory committee member John Maples said the "incredible, amateurish, irresponsible, dodgy dossier" was what had caused Mr Campbell's "problem".
Mr Campbell said the "dodgy dossier" should not be used to define the totality of the huge amount of communication between the prime minister, Parliament and the public.
"There is a legitimate place within the political process for dealing with issues of presentation ... now we have a 24 hour media, round the world, round the clock," said Mr Campbell.
Mr Campbell said there were large parts of the media that had an agenda on Iraq which was largely open.
But Mr Campbell said in the BBC there was a "disproportionate focus on the descent, the opposition, to our position". During the conflict, the prism within the BBC was one of "it's all going wrong", he said.
Now the conflict had not led to the Middle East going up in flames .... "those same people have to find a different rationale", said Mr Campbell.
Mr Campbell said most days during the conflict, he and Jonathan Powell, Downing Street's chief of staff, would go and see the prime minister very early in the morning to discuss what he was going to do during the day. "The idea that because I am a special adviser, somehow there is something terrible about that or the idea that I am doing it for political reasons ..." he said.
Mr Campbell said he was going to "keep going" until he receives an apology from the BBC over Andrew Gilligan's allegations.
Mr Campbell said some of the "best journalism" during the conflict "was from the BBC". But when there was bad journalism, the BBC has a responsibility to deal with that.
"I find it incredible that people can report, based on one single, anonymous, uncorroborated source ... that the prime minister, the Cabinet, the intelligence agencies, people like myself, connived to persuade Parliament to send British forces into action on a lie," said Mr Campbell.
"Until the BBC acknowledges that's a lie, I will keep banging on and that correspondent's file will get thicker," said Mr Campbell.
Mr Campbell said he "can go days and weeks without seeing intelligence".
Tory committee member Sir John Stanley asked for a list of the drafting amendments Mr Campbell proposed to the September 2002 dossier, as it evolved. He asked for those to detail what was accepted by the Joint Intelligence Committee and what was not.
Mr Campbell said releasing those details was dependent on the approval of the Joint Intelligence Committee.
Mr Campbell said he took responsibility for the February document. "I have explained why the mistake was made. I am happy to send an apology to Dr al-Marashi," said Mr Campbell, adding that this would be on behalf of the communications team at Number 10 and the Communications Information Centre.
"We are involved in an awful lot of pieces of communication and when we make a mistake, we hear about it for quite a long time," said Mr Campbell.
"I don't think we have made that many mistakes. This was a mistake that we have acknowledged many, many times," said Mr Campbell, who said the person who made the mistake "feels wretched about it". "I know that, because I work with the guy," he added.
Sir John said as long as Mr Campbell has his fingerprints on Joint Intelligence Committee sourced documents, that was not conducive to the integrity of the intelligence service.
"I suspect that is because you may be not persuaded by my integrity in relation to the work that I do," said Mr Campbell. "And that, if true, from my perspective, is regrettable."
Mr Campbell said he could not recall seeing any assessment from intelligence sources that suggested that Iraq was not an immediate threat.
"Nobody was ever saying that Iraq was going to whack off a missile at Peterborough," said Mr Campbell.
Asked by committee chairman Donald Anderson who its members should believe, Andrew Gilligan or him, Mr Campbell said he worked in "a pretty exposed position and I work with a prime minister who is answerable to Parliament".
"The one thing you don't do if you are an elected politician is lie to the House of Commons," said Mr Campbell.
He said the allegation made by the BBC was "that the prime minister did exactly that", that he had put to the country and to Parliament a false basis for putting at risk the lives of British servicemen.
Mr Campbell said he was used to be described "in all sorts of ways", adding: "I simply say, in relation to the BBC story - it's a lie. It was a lie. It is a lie that is continually reported." He will keep on until he gets an apology for it, said Mr Campbell.
The session ended at 1808 BST with Donald Anderson concluding: "Mr Campbell, this is the committee's first meeting with you - I hope it will not be the last."
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