Brown, appearing just weeks before an election to discuss a war that still rankles with many Britons, acknowledged the human cost of the conflict, said mistakes had been made in the chaotic aftermath of the invasion but distanced himself from the most contentious decisions.

"I believe we made the right decision for the right reasons," Brown told the five-person inquiry that he set up last year to learn lessons from the conflict following the withdrawal of British troops.

Brown said that former Iraqi dictator Saddam Hussein was a "serial violator" of international law and that tackling him had been an important test for world powers after the Cold War.

"Obviously the loss of life is something that leaves us all sad, the loss of life particularly after the success of the initial military operation to remove Saddam Hussein is something that leaves me very sad indeed," he said.

Commentators say Brown can expect some uncomfortable headlines from his appearance at the inquiry but do not believe it will cause him or Labor any lasting electoral damage.

They argue most Britons who were deeply opposed to the Iraq war had already abandoned Labor at the 2005 election.

Reuters