More than six years after the invasion of Iraq, a long awaited official enquiry into Britain's role in the war has begun hearing evidence. It will examine Britain's involvement in the run-up to the invasion, the conflict itself and its aftermath. On the first day of public hearings, four senior diplomats and advisers gave evidence on the war's origins. Sir Peter Ricketts, a top intelligence official at the time, said it was assumed it was not Britain's policy to remove Saddam Hussein in early 2001 despite concerns about his threat.The inquiry chairman has said he hopes to conclude his report in late 2010. Relatives of some of the 179 UK service personnel killed in Iraq gathered outside the venue in central London where the hearings are being held, as did a number of anti-war protesters.