KABUL: US Defence Secretary Ashton Carter landed in Afghanistan Friday on an unannounced visit, as uncertainty lingers over President-elect Donald Trump's strategy on America's longest war with no end in sight.

Carter is expected to meet Afghan President Ashraf Ghani and American troops on his last official trip to Afghanistan before he hands over the reins to Trump's pick for Pentagon chief, the hardline retired general James Mattis.

Copyright AFP (Agence France-Press), 2016