The shocking revelation from the recently retired intelligence officer adds yet another blow to the Bush administration and its coalition members.
The US, Britain and Australia are coming under increasingly intense scrutiny as their leaders attempt to justify the invasion of Iraq.
Greg Thielmann retired in September from his post as director of the Strategic, Proliferation and Military Affairs office in the State Department’s Bureau of Intelligence and Research.
“The Bush administration did not provide an accurate picture to the American people of the military threat posed by Iraq,” said Thielmann on Wednesday.
“Some of the fault lies with the performance of the intelligence community, but most of it lies with the way senior officials misused the information they were provided,” he said at a new conference held by the Arms Control Association.
Bush, along with staunch allies London and Canberra, justified the war against Iraq in March on claims Baghdad posed a global threat because of its alleged possession of weapons of mass destruction (WMD).
Since US troops occupied Baghdad on 9 April, they have found no such arms.
Central Intelligence Agency (CIA) Director George Tenet also made “some inaccurate formulations” when he told Congress that Iraq “retains” a small number of Scud missiles, said Thielmann.
The intelligence community said Iraq “probably” had Scuds because some could not be accounted for, he added.
"...senior officials misused the information they were provided".
Greg Thielmann, retired State Department intelligence official
There is mounting pressure on Washington, London and Canberra to provide evidence of Iraq’s alleged illegal weapons.
But according to senior British government officials, no such weapons will be found.
The British Broadcasting Corporation (BBC) quoted senior sources as saying they did not believe that “physical weapons of mass destruction are actually going to be found” said political editor Andrew Marr.
In Australia, a key intelligence agency revealed on Thursday that it knew of US doubts that Iraq had sought to buy uranium for an alleged nuclear weapons programme but failed to pass the information on to the government.
The secretive Office of National Assessments (ONA) made the statement as Prime Minister John Howard came under fire for using a faulty nuclear report to justify Canberra’s participation in the war.
The ONA said it learned in January that the US State Department had doubts over a British intelligence report that ousted Iraqi President Saddam Hussein had sought to buy uranium from Niger.
The agency said it mentioned the uranium acquisition claim in a single report for the government in December.
Howard has repeatedly referred to the allegation in laying out his justification for war against Baghdad.