Key dates since the start of the 2001 war in Afghanistan and efforts to broker peace

FILE PHOTO: An Afghan man wearing a protective face mask walks past a wall painted with photo of Zalmay Khalilzad, U.S. envoy for peace in Afghanistan, and Mullah Abdul Ghani Baradar, the leader of the Taliban delegation, in Kabul, Afghanistan April 13, 2020.REUTERS/Mohammad Ismail/File Photo

KABUL (Reuters) - An Afghan grand assembly, known as the Loya Jirga, on Sunday approved the release of 400 "hard-core" Taliban prisoners, a decision endorsed by President Ashraf Ghani, paving the way for peace talks between the government and the insurgents aimed at ending a 19-year war.

Following is a chronology of U.S. involvement and major developments in Afghanistan over the past 19 years. The Afghan war has killed more than 2,300 U.S. service members and wounded more than 20,000, while more than 100,000 Afghan civilians are estimated to have died.