Scarlett will be asked to justify reliability of 45-minute claim

Pressure on inquiry witness after Independent revealed doubts about his evidence

The Iraq inquiry committee has come under pressure to recall Britain's former spy chief to give further public evidence after allegations that he misled them over Saddam Hussein's ability to use weapons of mass destruction.

Sir John Scarlett, who oversaw the drafting of the government's controversial 2002 dossier outlining the case for invading Iraq, had claimed that intelligence indicating that Iraq could launch missiles within 45 minutes was "reliable and authoritative". But Dr Brian Jones, the most senior WMD analyst who saw the original intelligence, told The Independent that it was vague, inconclusive and unreliable.

MPs from all parties raised concerns about the evidence given by Sir John. He was already due to return to give private evidence to the inquiry in the New Year. Now it is understood that he will be asked again about the validity of the strength of the intelligence behind the 45-minute claim in the session, which will be behind closed doors unless the inquiry bows to pressure to make it public.

Ed Davey, the foreign affairs spokesman for the Liberal Democrats, said that the inquiry's previous failure to ask Sir John about the source of the 45-minute claim was "clearly a major error" that should be rectified. "The idea that this issue should be examined in private beggars belief," he said. "It's clear that the inquiry should hear again from Scarlett in public on this issue. They would be well advised to also invite Dr Brian Jones to give evidence."

Clare Short, now an independent MP who resigned from the Cabinet after the Iraq invasion, also said that Dr Jones needed to give evidence. "It is outrageous that he has not been called yet," she said. "If he contradicts earlier evidence, they will either have to call back John Scarlett or choose who they believe."

Paul Flynn, Labour MP for Newport West and a fierce critic of the decision to go to war, said that Sir John should be recalled "without a doubt" as the 45-minute claim had been central in convincing unsure MPs and the public to back the war. "There were many MPs who would have changed their minds over supporting the war if it hadn't been for the 45-minute threat, but took the view that they had to believe the secret services," he said.