Tony Blair has made his long-awaited appearance before the UK's inquiry into the Iraq war. Here are his answers to the key questions.
Tony Blair: "In the end it was divisive and I'm sorry about that"
At the end of the six-hour session, inquiry chairman Sir John Chilcot asked Mr Blair whether he had any regrets over Iraq.
"In the end it was divisive and I am sorry about that. I tried my level best to bring people back together again."
"But if I am asked whether I believe we are safer, more secure, that Iraq is better but our own security is better, with Saddam and his two sons out of power and out of office, then I believe, indeed, that we are."
"Responsibility but not a regret for removing Saddam Hussein. I think that he was a monster, I believe he threatened not just the region but the world and in the circumstances that we faced then, but I think even if you look back now, it was better to deal with this threat and to remove him from office.
"I do genuinely believe that the world is safer as a result."
The 9/11 attacks "dramatically changed" his thinking about what must done about Iraq, Mr Blair said, even though there was "no evidence" of links between Saddam Hussein and Al-Qaeda.
"Up to 11 September, we thought he [Saddam Hussein] was a risk but we thought it was worth trying to contain it.
"If 11 September had not happened our assessment of the risk of allowing Saddam any possibility of him reconstituting his programmes would not have been the same. After 11 September, our views, the US view, changed and changed dramatically.
"The point about this act in New York was that had they been able to kill even more people than those 3,000 they would have. And so after that time, my view was you could not take risks with this issue at all."
Mr Blair said the policy of trying to "contain" Iraq through sanctions had been steadily "eroding" and a plan for "smarter" sanctions, focusing on a specific list of prohibited items, was unlikely to work.
"This new framework of sanctions, to get it through the UN, had been watered down. Did I really think that a new sanctions framework was going to do the trick? No I didn't."
"I couldn't describe the nature of the threat in the same way if I knew then what I know now"
There have been suggestions at the inquiry, partly prompted by a recent Fern Britton interview, that Mr Blair favoured regime change rather than being focused purely on disarming Saddam Hussein of his weapons of mass destruction. He said there was danger of "a binary distinction" between regime change and disarmament.
"The truth of the matter is that a regime that is brutal and oppressive - that for example has used weapons of mass destruction against its own people, as Saddam did, and had killed tens of thousands of people by the use of chemical weapons. Such a regime is a bigger threat if it has weapons of mass destruction than one that is otherwise benign."
He said he had not shifted his stance that the basis for war was Iraq's failure to comply with its obligations to disarm.
"I did not use the words regime change in that interview. It was the breach of the UN resolutions on WMD, that was the cause. It was then and it remains."
Mr Blair was asked about the 45 minute claim and what it referred to
Mr Blair was asked about the claim that Saddam Hussein could use chemical weapons within 45 minutes of giving an order included in the September 2002 dossier.
"I didn't focus on it a great deal at the time because it was mentioned by me and then, as I say, it was never actually mentioned again by me.
"It really assumed a vastly greater importance at a later time precisely because of the allegation, which was extraordinarily serious one that we, Downing Street, had deliberately falsified the intelligence which we, of course, had not."
But he said he should have responded to newspaper headlines by clarifying what the 45-minute claim referred to.
"It would have been better to have corrected it in the light of the significance it later took on."
Did Mr Blair stand by his claim, in the 2002 dossier, that intelligence had established "beyond doubt" that Iraq was continuing to produce chemical and biological weapons?
"What I believe the assessed intelligence has established beyond doubt is that Saddam has continued to produce chemical and biological weapons. I did believe it and I did believe it, frankly, beyond doubt.
"I think you would have been hard pressed to have found virtually anybody who doubted he had WMD and WMD capability."
SECOND UN RESOLUTION
The UK tried hard to secure a second resolution but he said ultimately the UK did not believe it was legally necessary to justify military action. He was asked why bother going for a second one if it was not needed.
"A second resolution was obviously going to make life a lot easier, politically and in every respect.
"It all revolved around the interpretation of [resolution] 1441 and the question was what did the Security Council mean?"
"When you analyse 1441 it said one last chance and he [Saddam Hussein] didn't cooperate. I am just telling you to go back and read 1441 - it's pretty obvious you can make a decent case for this.
"There was at least as powerful an argument on the side of one resolution only as there was against it."
He said he stood by his decisions saying the threat from Iraq would only have increased over time.
"Sometimes what's important is not to ask the March 2003 question, but to ask the 2010 question.
"Supposing we had backed off this military action. Supposing we had left Saddam and his sons, who were going to follow him, in charge of Iraq. People who'd used chemical weapons, caused the death of over a million people.
"What we now know is that he retained absolutely the intent, and the intellectual know-how to re-start a nuclear and a chemical weapons programme when the inspectors were out and the sanctions changed, which they were going to be.
"Now I think it's at least arguable, that he was a threat, and that had we taken that decision to leave him there, with the intent, with an oil price not of $25, but of $100, he would have had the intent, he would have had the financial means, and we would have lost our nerve."
LEGALITY OF WAR
Tony Blair said the legal case hinged on Saddam Hussein ignoring the "one last chance" he was given
Tony Blair was asked why Attorney General Lord Goldsmith changed his mind on whether a second UN resolution was needed for the war to be legal only a few weeks before the invasion.
"Peter [Goldsmith], in the end, decided that a case could be made out for doing this without another resolution.
"What I needed to know from him, in the end, was he going to say this was lawful. He had to come to a conclusion on this.
"He wasn't alone in international law in coming to that conclusion. He would not have done it unless he had believed it and thought it was the correct thing to do. For us and for our armed forces that was sufficient."
The inquiry heard about failures in the planning for post-war Iraq, with Mr Blair answering criticism about the lack of preparation from people such as former International Development Secretary Clare Short.
"We didn't take a cavalier attitude to planning in the UK."
"If we knew then what we know now we would, of course, do things very differently. But for what we thought we were going to have, we had planned for it and we met those eventualities."
"When we go into a nation-building situation in future, we will be far better prepared and far better educated than we were then."
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