A leading figure in Iraq's biological warfare programme in the 1980s has said that he and other scientists had lied to United Nations inspectors about Baghdad's efforts to produce toxins and germ weapons.

Iraq produced 'huge quantities' of liquid anthrax and botulinum toxin, which it concentrated 5 to 10 times with sulphuric acid and other preservatives, Nassir Hindawi, who is in the protective custody of Iraqi opposition leader Ahmad Chalabi, said.

"There were orders to destroy it. They destroyed some; whether all or not, I can't say," Hindawi told The New York Times in an interview.

However, there was not much cause for concern because the arsenals would have degraded quickly, he said.

"Even if it's all kept until now, don't worry about it," he said.

Iraq was never able to make dried anthrax, which would have made the spores far more durable and easier to disseminate, Hindawi, who was imprisoned during the final weeks of Saddam Hussein's rule, said.

Though he thought he had devised a way to turn liquid anthrax into powder, he said he did not do it.

"I kept the method secret. History would have cursed me."

Several UN inspectors questioned his assertion that Iraq had not made the powdered form of anthrax.

But Hindawi said if Iraq had made such a weapon, it must have done so after he left the scientific wing of the programme in 1989, the report said.

He also denied being aware of any Syrian-Iraqi cooperation on unconventional weapons. Iraqi scientists built their germ warfare programme themselves, he said.