The government is refusing to release a secret draft of its dossier on Iraq's supposed weapons of mass destruction.
It was claimed Iraq had weapons of mass destruction
The version was written by the Foreign Office's head of press, who said it did not include the infamous "45-minute claim", the New Statesman reported.
A charity worker has been trying to get it published for two years under the Freedom of Information Act.
He has appealed to the Information Commissioner but the Foreign Office says it has "no plans" to publish it.
The final version of the September 2002 dossier, part of government efforts to bolster support for the Iraq war, became controversial the following year because of its claim that weapons of mass destruction could be used by Saddam Hussein at 45 minutes' notice.
It later emerged it referred only to battlefield munitions, and the whole claim was officially withdrawn two years later.
The existence of another draft of the dossier, by Foreign Office media chief John Williams on 9 September, was alluded to during the Hutton Inquiry.
It is not clear how much it differs from the 10 September version of the dossier, which the Hutton Inquiry was told was the first drawn up under the ownership of the then Joint Intelligence Committee Chairman John Scarlett.
Mr Williams, who has since left the Foreign Office, told the New Statesman magazine he was "absolutely sure" the 45-minute claim was not in his draft.
Plaid Cymru MP Adam Price, who has been pushing for a Parliamentary inquiry into the war, said: "If the first draft of the now-infamous dossier was indeed penned not by a spook but a spin doctor, then all the government's denials in Hutton, Butler and beyond are exposed as just another layer of mendacity."
The Hutton Inquiry, prompted by the death of Dr David Kelly after he was revealed as the source of BBC claims about the dossier, concluded the government had not inserted the 45 minute claim into the dossier knowing it to be probably wrong, or against the wishes of the heads of the intelligeance services.
A Downing Street spokesman said "We have nothing to add to all the inquiries into this. It was all covered in the Hutton Inquiry."
A Foreign Office spokesman added that the decision not to disclose the Williams draft after a Freedom of Information request in 2005 had been upheld by an internal review.
He added the Foreign Office "remains satisfied that its application of the FOI Act was correct and has no plans to release the draft pending the outcome of the case before the Information Commissioner".
Information Commissioner Richard Thomas is considering the matter, and could order the dossier's disclosure.