Updated

NATO defense ministers are discussing the future of the alliance's operation in Afghanistan and how best to use its military presence to support political talks aimed at ending the conflict.

Frustrated with America's longest war, U.S. President Donald Trump says he wants to pull out troops, raising doubts about NATO's training operation in the strife-torn country.

Around 14,000 U.S. troops are in Afghanistan, just over half with NATO and the rest doing counter-terror and combat operations.

Were U.S. troops to leave the NATO operation, some allies, like Germany, wouldn't be able to do their job as they rely on American air support.

U.S. envoy Zalmay Khalilzad is meeting with the Taliban and others to try to end Afghanistan's 17-year war. He briefed NATO ambassadors before Thursday's meeting.