British forces have ceased combat operations in Iraq, handing over the role to U.S. troops. In London, Prime Minister Gordon Brown paid special tribute to the British service personnel who lost their lives during the six-year campaign.
As buglers played, the British command flag was lowered at their base outside of Basra and power was transferred to U.S. forces.
Marking the historic significance, the commander of Britain's 20th Armored Brigade, Brigadier Tom Beckett said goodbye.
"We are sad to leave our Iraqi friends but we leave knowing we have done our job, done it well and that we have prepared the ground for continued success for our friends and allies," he said.
In London, Prime Minister Gordon Brown called Britain's lengthy and controversial mission in Iraq a success and he paid tribune to the British service personnel who lost their lives there.
"Already today, the defense secretary has attended a moving memorial service to the 179 British personnel who have died serving their country in Iraq," said Mr. Brown. "They will always be remembered for the service they have given. Our country owes them a huge debt of gratitude."
The transfer of power in southern Iraq has come a month ahead of schedule. About 3,700 troops will now start to head home in a phased withdrawal.
At a London news conference, Mr. Brown stressed that Britain will continue to stand with Iraq.
"Today was not just about the past. It was about the future. Today the prime minister and I have signed a declaration of friendship, of partnership and cooperation between our two countries which sets out a new basis for the relations between Britain and Iraq," he said.
As Brown underlined, a big part of that relationship will concern business.
"Prime Minister Maliki will attend the Invest in Iraq conference here in London in which 250 of the world's biggest companies will be participating. We will also open negotiations on an investment, promotion and protection agreement," he said. "Bring forward a review of export credit guarantees offered to U.K. exporters wishing to trade with Iraq. And this is a clear message to companies worldwide, Iraq is open for business."
With the troops soon packing their bags, the question of the war's legacy in Britain is uncertain. It was an unpopular war and it lasted longer in duration than either of the two World Wars. Calls are growing for an immediate full inquiry into why Britain entered the war in the first place.
The leader of the opposition Conservative party says with the departure of British forces from Iraq now imminent, vital lessons need to be learned rapidly.