ABOARD HMS QUEEN ELIZABETH (AP) — NATO's head says the government and armed forces of Afghanistan are strong enough to stand on their own feet without international troops to back them.

“At some stage, it has to be the Afghans that take full responsibility for peace and stability in their own country,” NATO Secretary-General Jens Stoltenberg told The Associated Press in an interview Thursday.

NATO took charge of security efforts in Afghanistan in 2003, two years after a U.S.-led coalition ousted the Taliban for harboring former Al-Qaeda leader Osama bin Laden. The military alliance is scheduled to leave by Sept. 11, the 20th anniversary of the 2001 attacks on New York and Washington.

Many officials have expressed concern that once the U.S. leaves, the Afghan government and its armed forces will be quickly overrun by the Taliban. Violence has steadily mounted in recent months as the drawdown gathered pace.