As Tony Blair faces the Iraq Inquiry, former MP and war critic Tony Benn tells Channel 4 News what questions he would be asking and what he hopes will emerge from the inquiry.

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Tony Benn has campaigned against the Iraq invasion since 2003 and is president of the Stop the War Coalition.

Speaking to Channel 4 News, he said there was one key area which Sir John Chilcot must examine at the Iraq Inquiry: "The most important question to ask Mr Blair is this: why have you not allowed your messages or letters to George Bush to be published?"

He added: "I think the reason is this: at a very early stage I think Blair said to Bush 'I will follow whatever you do' but he didn't tell the public this. He kept saying that nothing was decided but actually I think he'd given Bush an assurance that he'd go along with it.

The Iraq Inquiry: as Tony Blair is questioned for a second time, get all the background from Channel 4 News

"That raises the whole question really as to what our relationships with America ought to be. There are so many detailed questions: when Blair saw Bush, what he said to him, what he told his colleagues, did he listen to the Attorney General?

"All these questions, if they're brought out, and I think they will be, will confirm the judgement of many people, including myself, that the decision to go to war was wrong."

The Iraq Inquiry

Tony Benn told Channel 4 News that he originally had doubts about the Iraq Inquiry because he thought it would be a cover-up.

He has since changed his mind, he said.

"When I look at what it's done, I think it has brought out some important things and the interrogation of Mr Blair today is going to be a very, very important one. It's a chance to bring out some of the things I've been talking about," he said.

"I think if that happens it will restore public confidence in the possibility of democratic change. Otherwise you're just a spectator of what is decided for you in your name by your leader and you know nothing about it. That's not a very happy position to be in."

Tony Blair is to give evidence to the Iraq Inquiry for the second time (Reuters)

The Blair legacy

Tony Blair made an appearance before the Iraq Inquiry in January 2010 where he said he was "sorry" that the war had been divisive.

But he mounted a vigorous defence of the 2003 invasion, insisting he had no regrets over removing Saddam Hussein and would do the same again.

I think people will remember Tony Blair for having started the war. That's the biggest thing in his life. Tony Benn

Tony Benn said that Tony Blair will forever be associated with Iraq: "I think people will remember Tony Blair for having started the war. That's the biggest thing in his life and he'll be remembered for that and I think condemned for that.

"I'm not in favour of war crimes tribunals because it's too easy to take one person and put the blame on him. In fact all the people who went along with the war in the Cabinet and elsewhere have to share responsibility with him.

"Tony Blair will have to live until the end of his life knowing he launched a war based on the theory, which was quite untrue, that Saddam had weapons of mass destruction."

Saddam Hussein

Tony Benn met Saddam Hussein on two separate occasions.

The first was in 1990 just before the Kuwait war. The second was in 2003 before the most recent invasion.

"I asked Saddam certain questions, such as do you have weapons of mass destruction, and he said 'no'. I didn't know whether to believe him but of course when the Americans went into Iraq they never found any weapons of mass destruction.

"At least I took the opportunity as an individual to try and find out the key questions and publicise them but they didn't influence Government policy."