British defense officials announced Wednesday that the country is officially ending its military mission in Iraq on Sunday, concluding an unpopular eight-year operation that led to the deaths of 179 British military personnel.

Although some British troops could still serve in Iraq as part of future NATO training obligations, Defense Secretary Liam Fox told the House of Commons that the 170 troops currently stationed in Iraq have successfully completed their mission to train Iraqi naval forces.

“Thanks to the sacrifice, commitment and professionalism of thousands of British service men and women, southern Iraq is an area transformed from the dangerous and oppressed place it was under Saddam Hussein,” Fox said.

Fox’s statement could renew debate in Washington about whether a continued U.S. military presence is needed to train and assist national security forces in Iraq, where violence has dropped substantially but bombings and assassinations remain routine.

At the peak of the U.S.-led invasion in 2003, Britain had 46,000 combat troops in Iraq, mostly in the southern port city of Basra. It withdrew its combat troops in July 2009, but a small number of troops remained behind to help train naval forces.

Brig. Max Marriner, commander of British Forces Iraq, said Wednesday, “U.K. armed forces can look back with pride at what they have achieved in Iraq since 2003.”

“Security has fundamentally improved and, as a consequence, the social and economic development of the south has dramatically changed for the better, as, too, have people’s lives,” Marriner said.

But the British military’s involvement in the Iraq invasion proved extremely unpopular domestically, sparking large street demonstrations and a backlash against Prime Minister Tony Blair, who resigned in 2007.

Under the terms of the pullout, British forces will continue to assist Iraqi naval forces from Britain, as well as supporting NATO training missions, Fox said. But by August, even Britain’s military support base in Kuwait will be disbanded, officials said.

In London, few people appeared to notice the news that the last troops would soon be leaving, as most British media focused on the second day of Queen Elizabeth II’s visit to Ireland.

But the announcement comes at a sensitive time for American and Iraqi officials trying to decide how quickly all U.S. forces will leave the country. About 47,000 troops remain in non-combat roles, but a three-year-old security agreement between Iraq and the United States calls for a complete withdrawal by Dec. 31.

Defense Secretary Robert M. Gates has indicated some troops could remain past the deadline if Iraq requests them. Iraqi Prime Minister Nouri al-Maliki has said Iraqi security forces are now capable of defending the country but recently stated that he is open to having some U.S. troops remain if there is consensus among the leaders of Iraq’s main political blocs.

Special correspondent Karla Adam in London contributed to this report.