U.S. Defense Secretary Mark Esper arrived Kabul in an unannounced visit.
This is Esper’s first trip to Afghanistan after becoming defense secretary.
Pentagon chief is due to meet Afghan leaders and U.S. troops while in Afghanistan.
According to the media reports, Esper has told reporters travelling with him that he believes the U.S. can reduce American forces in Afghanistan to 8,600.
But he said any pull out would happen as part of a peace agreement with the Taliban insurgent group.
Currently, the U.S. has about 14,000 troops in Afghanistan.
This comes after reports emerged that U.S. and Taliban representatives are discussing the resumption of peace talks.