British Prime Minister David Cameron pledged Tuesday to maintain an enduring partnership with Afghanistan, promising to increase aid even as British troops begin to withdraw next year, AP reported. At a news conference with Afghan President Hamid Karzai, Cameron vowed to increase Britain's aid to Afghanistan and help build an elite military academy modeled on England's famous Sandhurst. The British leader's visit to Afghanistan was marred by the death Monday of a British soldier, who went missing from a checkpoint in the south and was later found with fatal gunshot wounds. The death was a «reminder of the high price that we have paid for the vital work we do in Afghanistan,» Cameron said. Separately, the U.S.-led international military coalition said four service members were killed Tuesday in eastern Afghanistan _ three by a roadside bomb and one other in an insurgent attack. No other details were disclosed about the deaths, which raised the total killed so far this year to 280. Britain gave 102 million pounds ($164 million) of aid to Afghanistan between April 2010 and April 2011, and is expected to pay out 178 million pounds ($286.5 million) during the next 12 months.