U.S., U.K. combat troops end operations in Afghanistan's Helmand province

British troops and U.S. Marines officially ended their combat operations in Afghanistan's southern Helmand province on Sunday with ceremonies at the coalition's Regional Command (Southwest) combined base.

The U.S. and U.K. flags were lowered for the last time at the American Camp Leatherneck and adjacent British Camp Bastion as the compound that was once home to some 40,000 personnel was handed over to the Afghan military.

The timing of the withdrawal had not been made public earlier over concerns about security.

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The two countries made up the largest combat forces in Afghanistan since foreign forces invaded to topple the Taliban 13 years ago. The international coalition ends its combat mission at the end of the year. The last Canadian combat soldiers in Afghanistan left the country seven months ago.

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U.K. Defence Secretary Michael Fallon said the end of combat operations was announced "with pride" and that Britain helped give Afghanistan "the best possible chance of a stable future."

He said Britain's commitment to support Afghanistan will continue "through institutional development, the Afghan National Army Officer Academy, and development aid."

After the withdrawal, the Afghan National Army’s 215th Corps will be headquartered at the 6,500-acre base, leaving almost no foreign military presence in Helmand.

The province, which produces 80-90 percent of the opium that helps finance the Taliban’s insurgency, has seen fierce fighting this year, with Taliban and allied forces seeking to seize the district of Sangin from Afghan army and police.

The battles have raised concerns about whether Afghan forces are truly able to hold off the Taliban without intelligence and air support from the United States and its allies.

Officials with the U.S.-led coalition say the Afghan forces held their own this summer fighting season and did not lose any significant ground.

Brig. Rob Thomson, senior U.K. officer in Helmand, said Afghan National Security Forces are "more than ready" to assume responsibility for security.

On Sept. 30, newly elected Afghan President Ashraf Ghani Ahmadzai signed a security pact that will ensure a continued U.S. military presence in Afghanistan beyond 2014 to support the training of Afghan soldiers in the fight against the insurgency.