Barack Obama has extended the combat role for US troops in Afghanistan for another year, in a classified order he signed in recent weeks, according to reports.
Previously, the president had said US-led NATO combat operations would finish at the end of this year.
The NATO follow up mission, to take over on January 1 with 9,800 US troops and about 3,000 soldiers from Germany, Italy and other member nations, was to focus on supporting Afghan forces as they take on the Taliban, in parallel with US counter-terrorism operations.
But in a strategic shift, the New York Times said, Obama signed an order authorizing US troops through 2015 to carry out missions against militant groups, including the Taliban, that threaten them or the Afghan government.
The new order also allows for air support - from US jets, bombers and drones - for Afghan combat missions.