Iraqi chemical weapons posed no significant risk to Britain in the run-up to the war, according to a former head of the international body monitoring proliferation of the weapons.
Mr Ron Manley, who was director of verification at the Organisation for the Prohibition of Chemical Weapons (OPCW) and worked in Iraq, said it was unlikely the Iraqis had enough viable agents to arm more than a couple of missiles.
Any agents produced before the start of UN weapons inspections in 1991 would be useless by now, and there was no sign of the large factories that would have been needed to produce them after the inspectors' left in 1998, said Mr Manley.
Despite his expertise, Mr Manley, who retired from OPCW in 2001, said he had not been approached by British or US intelligence for his assessment of the risk posed by Saddam Hussein.
Asked by the BBC if Iraqi chemical weapons posed a threat before the war, he responded: "Not really, no". He said: "There were only two real scenarios which anyone considered - either there were weapons hidden from 1991 or they were manufacturing weapons after 1998.
"If there were weapons from before 1991 hidden in Iraq, knowing what we know about Iraqi agents and the chemistry of their agents, these weapons would be useless by today because of decomposition.
"If they were manufacturing after 1998, then I think the question is where? You can't make chemical weapons of military significance in a small room. You need big chemical infrastructure and that sort of infrastructure would be seen," he said.
There was no doubt that Saddam had previously produced chemical weapons and would have done so again given the chance, Mr Manley added.
But he added: "My view at the start of the war was that there might have been a few odd weapons left over from previous times . . . but I don't believe there was any significant stocks of materials".
PA