Panetta arrived Wednesday on an unannounced visit to Kabul to consult with top military commanders as well as confer with Karzai.
The visit comes at a difficult juncture in the Western coalition’s efforts to shift more security responsibilities to Afghan forces so the combat mission can end in December 2014.
While security has generally improved lately, the Afghan government’s ability to effectively govern and to root out corruption is in great doubt. Peace talks with the Taliban are on a back burner.
Speaking to reporters earlier Wednesday in Kuwait, Panetta did not reveal what options Obama is considering, but officials have said he may settle on a figure between 6,000 and 10,000 troops. There currently are about 66,000 U.S. troops in Afghanistan.
The post-2014 mission is expected to focus on counterterrorism and advising Afghan security forces.
Before flying to Afghanistan, Panetta spoke to about 100 U.S. service members inside an aircraft hangar at a desert base west of Kuwait City. He thanked them for their service and emphasized that the U.S. is winding down its involvement in lengthy wars.