He resigned when he says his reports were censored by the CIA.

In the ABC interview Mr Barton also details how he notified Australia's Defence Department of prisoner abuse in Iraq.

Hamish Fitzsimmons reports.

HAMISH FITZSIMMONS: Rod Barton was seconded from Australia's Defence Intelligence Organisation to work for UNSCOM, the United Nations body meant to ensure Iraq had destroyed any weapons of mass destruction.

He's told Four Corners in January 2003 he advised the Australian Government that intelligence it had received on Iraq's weapons capabilities was wrong.

ROD BARTON: My belief was that they had a few weapons retained from 1991, which would be ageing weapons of limited use. Were they a threat? Well, they may have been a minor threat to their neighbours, because don't forget they didn't really have the delivery systems in. They didn't have an air force. They may have been a minor threat to their neighbours, but a threat to the United States, or the UK or Australia? No.

REPORTER: And did you give the assessment that you've just given me?

ROD BARTON: Yes. That's the advice I gave.

REPORTER: No capacity to deliver?

ROD BARTON: Yes, yes. I mean what countries do with this advice is up to them.

HAMISH FITZSIMMONS: In October 2003, the Prime Minister John Howard said the intelligence on Iraq's WMDs was unambiguous.

Mr Barton also backs allegations the British Government embellished intelligence to claim Saddam Hussein's Iraq could deploy chemical and biological weapons within 45 minutes

He remembers a dinner with David Kelly, the scientist who committed suicide after he was outed as the source of the claims

ROD BARTON: I challenged him. I said, you know, what's this nonsense about this 45… I said, why did you write this David, knowing full well that David would not have written about the 45 minutes. And he was quite embarrassed and he said, oh well, some people put in what they want to put in.

HAMISH FITZSIMMONS: In 2003, Rod Barton was working as a special adviser to David Kay, the Director of the US Iraq Survey Group

David Kay left Iraq early, as soon as it became obvious to him there were no weapons of mass destruction.

DAVID KAY: It turns out we were all wrong probably, in my judgement, and that is most disturbing.

HAMISH FITZSIMMONS: Rod Barton says after US officials told him what information to include or exclude from his reports, he resigned in protest and made Australia's Defence Department aware of his reasons by March 2004.

ROD BARTON: I wanted to make it clear to them I'd left because I thought the process was dishonest.

REPORTER: And what was their response?

ROD BARTON: They were happy for me being there, because the Americans had requested me. And now, as far as they were concerned, I had disappointed the Americans because I'd left in this manner, quitting.

HAMISH FITZSIMMONS: Mr Barton also says he warned the Australian Government that Australians in Iraq were aware of, and even present during the abuse of prisoners by Coalition forces.

Mr Barton says he saw direct evidence of abuse and notified the Defence Department.

He says he was annoyed by Defence Minister Robert Hill's claims in June 2004 that no Australians were involved in the interrogation of prisoners nor did the government have any knowledge of prisoner abuse.

ROD BARTON: My prisoner abuse wasn't at Abu Ghraib. It was at Camp Cropper, the special prison for high value detainees. So what Hill said to Parliament was correct in the sense that he referred only to Abu Ghraib. But of course, he knew about this other prison, where I'd already reported prisoner abuse.

He left the impression that the prisoner abuse had only been at Abu Ghraib and he didn't know about anything else, and that I felt was dishonest. He would have known by then because the department had done a full investigation. I provided all my information.

TONY EASTLEY: Former intelligence analyst Rod Barton. That story airs on Four Corners at 8:30 this evening on ABC television.

AM approached Defence Minister Robert Hill for a response to Mr Barton's allegations, but he declined our request for an interview, saying he wanted to first see the Four Corners program in its entirety.

Through a spokeswoman, Senator Hill also denied misleading Parliament, saying "there is nothing I have heard to date that would suggest there was any error or omission in relation to matters that were put before the Parliament".