The 45-minute warning related to smaller range munitions, a fact that may have caused Dr David Kelly, the subject of the Hutton inquiry, to be in a "state of genuine confusion about what the report actually said".
The disclosure by Prime Minister Tony Blair's most senior intelligence adviser is the first official statement on the exact nature of the threat.
Weapons experts said yesterday that the normal definition of an international weapons of mass destruction threat would exclude battlefield mortar shells, even if they had chemical or biological stocks attached. Such arms represented no threat to Britain, they said.
During the tense examination of Scarlett yesterday, the inquiry was told the intelligence agencies had been issued with an 11th-hour appeal for more evidence to strengthen the Government's dossier.
Hutton was told the agencies were asked to find more evidence of Iraqi arms programmes because No 10 wanted the dossier to be "as strong as possible".
Scarlett acknowledged that Alastair Campbell, the Government's director of communications and strategy, had asked if some of the dossier language could be "tightened".
He also confirmed that he had helped Campbell to prepare for his appearance before the Commons foreign affairs committee on June 25 and that Campbell had chaired two meetings on September 5 and September 9 on the presentation of the dossier. However Scarlett stressed that he himself had been in control of the intelligence content of the document.
He said the document had been designed to show the intelligence assessment available to ministers, and was not intended to make the case for war.
Last night (NZT), Defence Minister Geoff Hoon, the first cabinet member to appear before the inquiry, took the stand.
Hoon, seen as the most likely Government "fall guy" in the Kelly affair, faces questions about how the scientist's name was made public after he admitted briefing a BBC reporter who alleged that Blair's Government "sexed up" the Iraq dossier.
In opening testimony, Hoon said he had met Kelly by chance in April and discussed Iraq - without realising he was the Government's weapons expert.
"We discussed the Government's policy, which Kelly said he strongly supported," Hoon said.
Blair will take the stand tomorrow to answer allegations by a BBC reporter three months ago that his Government "sexed up" the threat from Iraqi weapons.
Scarlett's evidence
* John Scarlett said the 45-minute claim came from a single source who was quoting what he had heard from a senior Iraqi military official.
* Scarlett insisted the intelligence claim was based on "an established and reliable line of reporting".
* The intelligence "was consistent with established judgments on Iraq's experience and capability in the use of chemical and biological weapons".
* Scarlett repeatedly insisted that responsibility for the contents of the intelligence dossier was his alone.
- INDEPENDENT, REUTERS
Hutton inquiry website
British Parliament Foreign Affairs Committee transcript:
Evidence of Dr David Kelly
Key players in the 'sexed-up dossier' affair
Herald Feature: Iraq
Iraq links and resources
