U.S. Sen. Carl Levin, D-Mich., chairman of the Senate Armed Services Committee, said Sunday on CBS's "Face the Nation" that future U.S. troop needs in Afghanistan will be determined by variable factors, including how many soldiers are committed by NATO allies.
"It is too early to know what Congress would do," Levin said. "It depends on what the facts and the arguments are. It depends what our commanders in the field say. It depends also I think in part what our NATO allies are willing to do."
Levin noted that many U.S. allies have been reluctant to send more troops into the Afghanistan fight, and promised they will be strongly urged to do so.
"Many of (the NATO countries) have come forth," he said. "Some of them -- a number of countries have taken very hard hits, losses of troops, but a lot of the other NATO allies have fallen short of their commitments, and we're going to put maximum pressure on them to do what they promised to do."
Notable deaths of 2014 [PHOTOS]