The White House has taken the unusual step of releasing intelligence documents intended to prove that President George W Bush did not exaggerate the threat posed by Iraq before the war.
Bush and Blair say history will vindicate them
The October 2002 report said there was "compelling evidence" that Iraq had sought uranium for nuclear weapons.
But it also reveals the dissent expressed by the State Department's intelligence arm which describes the claims that Iraq was seeking uranium from Africa as "highly dubious".
The claim has been discredited by the United Nations as being based on forgeries and the White House has admitted it was a mistake to include the claim in Mr Bush's State of the Union address.
The head of the CIA has taken the blame.
The National Intelligence Estimate is a US intelligence summary based on the work of six agencies.
The summary said that "most agencies believe that Saddam's personal interest in and Iraq's aggressive attempts" to obtain nuclear weapons materials "provide compelling evidence that Saddam is reconstituting a uranium enrichment effort for Baghdad's nuclear weapons programme".
The report cites "high confidence" within the intelligence community that "Iraq could make a nuclear weapon in months to a year once it acquires sufficient weapons-grade fissile material".
However, under a category of "moderate confidence," the document states that "Iraq does not yet have a nuclear weapon or sufficient material to make one but is likely to have a weapon by 2007 to 2009".
Mr Bush's State of the Union address in January included a British Government claim that Iraq tried to get uranium from the West African state of Niger.
The CIA had voiced doubts about the intelligence long before the speech - and had cut it from an earlier presidential address - as did the State Department.
The Department's Bureau of Intelligence and Research (INR) said that "the claims of Iraqi pursuit of natural uranium in Africa are, in INR's assessment, highly dubious".
Tenet has taken the blame for not deleting the uranium reference from the speech
Explaining the decision to release the classified document, a very senior White House official said the material showed that general concerns about Iraq's nuclear programme were genuine, even if the president's specific reference to uranium may in hindsight have been a mistake.
The British Government has stood by the claim.
The uranium row was further fuelled on Thursday when a Democrat member of the Senate Intelligence Committee alleged that CIA Director George Tenet had accused a White House aide of pushing for the inclusion of the uranium claim in the speech.
The committee questioned Mr Tenet behind closed doors on Wednesday.
The BBC's Rob Watson says the release of this document shows just how anxious the White House is to silence its critics and how worried it is about the damage already done.
At this stage, though, it seems only the discovery of proscribed weapons in Iraq will end the debate, our correspondent says.