The 30-page draft - drawn up by the Foreign Office's then-communications director John Williams - was released after the Government lost an appeal last month against a ruling that it should be disclosed under the Freedom of Information Act.

The document was not released to Lord Hutton's inquiry into the death of Government weapons expert, Dr David Kelly, as the Government argued that it was not relevant to the investigation.

According to officials, it was quickly set aside after it was decided that the then-chairman of the Joint Intelligence Committee, Sir John Scarlett, should be made responsible for the document. However, shadow foreign secretary William Hague said that was fresh proof the Government had "spun" the case for war and underlined the case for a full, Privy Council inquiry.

"This is yet further evidence that spin doctors, not intelligence analysts, were leading from the first in deciding what the British people were told about Iraq's weapons of mass destruction," he said.

Liberal Democrat foreign affairs spokesman Edward Davey said the release of the draft showed that it contained the same "core analysis" as the final, published version.

"The Government cannot continue to deny the major role that spin doctors played in creating this dossier," he said. "A press official should never have been drafting a document that ended up being used as the justification for going to war."

Foreign Secretary David Miliband said that Mr Williams' paper "was not commissioned as part of the formal drafting process and was not used as the basis for the dossier which the Government subsequently published".

The draft refers to intelligence claims that Iraq had acquired uranium, retained the chemical precursors and production equipment to make chemical weapons, was self-sufficient in the technology required to produce biological weapons and was developing long-range missiles capable of threatening Nato.

However, there is no reference to the infamous claim that Iraq could launch its weapons of mass destruction within 45 minutes which appeared in the final, published version of the dossier.