The government is facing renewed calls for a full judicial inquiry into its decision to go to war with Iraq.
The weapons expert said Iraq was a threat to its neighbours
It follows Wednesday night's Panorama programme, on BBC One, which contained a previously unseen interview with the late weapons expert Dr David Kelly.
Dr Kelly said Iraq could deploy weapons of mass destruction within days or weeks, rather than the 45 minutes mentioned in a government dossier.
The Conservatives said the interview reinforced the case for a full inquiry.
Tory defence spokesman Michael Ancram said Dr Kelly's comments in the interview "do place his views at odds with those presented in the government's September dossier".
It was a "great shame" that the remarks had not been presented publicly as evidence to the Hutton inquiry into the arms expert's death, he said.
Dr Kelly apparently committed suicide after being named as the suspected source for a BBC story on claims Downing Street "sexed up" the government's Iraq weapons dossier.
The interview showed that he had been concerned over a passage amended by Downing Street chief of staff Jonathan Powell to suggest that Saddam Hussein would use weapons of mass destruction in circumstances other than self-defence, Mr Ancram said.
"This interview reinforces the case for the full independent judicial inquiry
into the run-up to the Iraq war which we have been calling for."
Liberal Democrat foreign affairs spokesman Sir Menzies Campbell said: "These
comments clearly underline Dr Kelly's scepticism about the government's claim of
an immediate threat.
"Nearly a year after going to war the Government has not been able to justify
its cause for doing so."
Downing Street refused to comment on the broadcast, in line with
its policy of staying silent until Lord Hutton has reported, next week.
The interview with Dr Kelly was recorded for Panorama in October 2002, a month after the prime minister presented the dossier to Parliament, but never broadcast.
In the interview Dr Kelly was asked whether there was an "immediate threat" from Saddam Hussein's weapons of mass destruction.
He replied: "Yes there is. Even if they're not actually filled and deployed today, the capability exists to get them filled and deployed within a matter of days and weeks. So yes, there is a threat."
He also said Saddam Hussein's biological weapons programme posed a "real threat" to neighbouring countries.
Dr Kelly was publicly generally supportive of the Blair government's tough stance on Iraq in the interview, which was submitted to the Hutton inquiry.
But he says Saddam Hussein would probably be reluctant to use weapons of mass destruction unless attacked first.
BBC correspondent Nicholas Witchell said the programme made "very uncomfortable" viewing for the BBC.
"What the BBC will be hoping is that the best way to demonstrate the strength, and it would say the integrity, of its journalism, is to be seen to be reporting very robustly, very fully and very candidly, on a story which does in some respects reflect badly on it," he told BBC News at 10.
Panorama also said BBC executives who stood by Andrew Gilligan, the reporter behind claims the government "sexed up" its dossier, without checking his original notes "bet the farm on a shaky foundation".