Iraq destroyed all its weapons of mass destruction 10 years ago, according to the United Nations' chief weapons inspector.
Dr Hans Blix searched for illegal chemical and biological weapons before the war.
He said the US and Britain's claims that Saddam had these weapons were "risky".
The US and Britain went to war with Iraq because their governments said Saddam was a threat.
Lying?
Dr Blix's statement could make them look like they were lying.
This comes as US President George Bush said there was no proof Saddam Hussein had any link to the 11 September 2001 attack on the Twin Towers in New York.
Many Americans believe Saddam had something to do with the attack.
Some people have accused the US Government of deliberately confusing people over this, so they would support the war.
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