Gates was greeted in Afghanistan by Gen. David McKiernan, commander of the NATO-led International Security Assistance Force. The two planned to share a working dinner, CNN reported.
Earlier in Saudi Arabia, Gates said he discussed the possible transfer of Yemeni terror detainees being held at Guantanamo Bay, Cuba, to Saudi rehabilitation centers.
The defense secretary told CNN he had a "positive impression of the rehabilitation program in Saudi Arabia," adding, "I think they've done as good or better job with that than almost anybody."
But he reportedly emphasized no formal offers have been made on detainees.