美国新任国防部长卡特前往阿富汗南部地区

New U.S. Defense Secretary Ashton Carter traveled to southern Afghanistan Sunday to review plans to withdraw U.S. troops from the country within two years.

On his second day in Afghanistan, Carter few to Kandahar from the capital, Kabul, where he had held a series of talks Saturday with Afghan leaders and American military commanders.

Carter is in Kandahar to receive briefings from U.S. and Afghan commanders on progress in training Afghan security forces.

Carter said the United States is "rethinking details" of its counter-terrorism mission in Afghanistan, including whether to slow down the withdrawal of U.S. troops, whose mission is changing from combat to training as Afghan troops take on responsibility for the fight against the Taliban.

He told reporters the issue is on the agenda when Afghan President Ashraf Ghani visits Washington next month.

Carter met with President Ghani, discussing both the drawdown and Afghan efforts to fight the Taliban. President Ghani told reporters that prospects for peace with the Taliban are better now than they have been in more than three decades, although he gave few details. He said "the direction is positive" but added he would not make "premature announcements."

Carter is also scheduled to meet with U.S. troops during his visit.

About 10,000 U.S. troops are in Afghanistan.