President Biden will withdraw all American troops from Afghanistan over the coming months, U.S. officials said, completing the military exit by the 20th anniversary of the Sept. 11, 2001, attacks that drew the United States into its longest war.

Biden’s decision comes after an administration review of U.S. ­options in Afghanistan, where U.S.-midwifed peace talks have failed to advance as hoped and the Taliban remains a potent force despite two decades of effort by the United States to defeat the militants and establish stable, democratic governance. The war has cost trillions of dollars in addition to the lives of more than 2,000 U.S. service members. At least 100,000 Afghan civilians have been injured or killed.