The admission, made in an unusual public statement by the Office of National Assessments (ONA), provided welcome relief to Prime Minister John Howard, who has been under fire this week for using the faulty uranium report to help justify Australia's participation in the war on Iraq.

But Howard said Thursday that even if he had been made aware that the US did not believe the uranium story, it would not have made any difference to Australian involvement in the war.

"If I had been told in January of this material, it would not have altered in any way our decision to participate in this operation," Howard said.

In its statement, the ONA said it became aware in January that the US State Department had doubts over a British intelligence report that Iraqi leader Saddam Hussein had sought to buy uranium from the African nation of Niger.

The secretive agency, which processes intelligence reports for the prime minister's office, said it had mentioned the uranium acquisition claim in a single report for the government in December.

"ONA became aware in January 2003 that the State Department was doubtful of the claims that Saddam Hussein had sought uranium from Africa," the agency said.

"ONA's reporting to the government did not refer to this State Department view and ONA did not inform the government of its awareness of this State Department view," it said.

Howard has been battling critics since the White House over the weekend admitted President George W Bush should not have included the uranium claim in a January State of the Union address laying out the justification for going to war against Iraq.

Before Bush's speech, US officials had learned from a US diplomat sent to Niger to check on the story that it was untrue.

Howard himself repeatedly referred to allegations Iraq was trying to develop nuclear weapons and referred to the African uranium claim in a key February speech justifying his decicion to join the war.

The Australian, US and British governments have all been under building criticism in recent weeks over their pre-war claims that Saddam's regime was hiding weapons of mass desctruction.

Since the fall of Saddam in April, no evidence of banned weapons has been found.

ONA said it had not been informed of the visit to Niger by the US diplomat, Ambassador Joseph Wilson, and that the US State Department's doubts about the story were referred to only once in an annexe to an 86-page document forwarded to the Australians.

Howard defended the agency, saying it dealt with "literally acres of raw intelligence every day".

Howard also noted that British intelligence continued to stand by their claim that Iraq sought to buy uranium from Africa, even if a key document concerning Niger was found to have been forged.

The Australian opposition said the ONA admission highlighted multiple errors of judgement by the government and its intelligence agencies surrounding Iraq.

The leader of the Greens party, Senator Bob Brown, accused the ONA of making it's admission now only to avoid being caught out by a parliamentary inquiry into pre-war intelligence on Iraq due to begin next month.

"They've decided it was less politically damaging to announce it now," he said. "They are in damage control for the prime minister's sake."

WAR.WIRE