Democratic presidential hopeful Mr John Edwards called for an independent commission to investigate if the Bush administration misled the US Congress in making its case for war with Iraq and demanded an end to "war profiteering."
The senator from North Carolina was responding to remarks by former chief US arms hunter Mr David Kay, who said after stepping down on Friday that he had concluded there were no stockpiles of biological and chemical weapons to be found.
"It's a serious issue and it's why I have called for an independent commission to investigate the discrepancy between what's found there and what we were told before," Mr Edwards told reporters in New Hampshire before next Tuesday's primary.
Edwards voted for the congressional resolution authorizing US President George W. Bush to wage war against Iraq.
Asked if he felt the Bush administration had misled lawmakers when making its case for war, Mr Edwards said, "That's exactly why ... we need an independent commission to get to the bottom of this."
Before the war, the Bush administration said it feared Iraq was stockpiling weapons of mass destruction. But Mr Kay said on Friday, "I don't think they existed."