“He said that he was willing to upgrade the capabilities of the Free Syrian Army,” McCain said in an interview with The Daily Beast, referring to the largest of the rebel groups. “This was a shift in the president’s thought and actions from before.”

McCain and Graham have said they want to know the president’s broader strategy for the Syrian conflict before voting on the war authorization.

Obama didn’t say which weapons he would give the rebels, but McCain said the Free Syrian Army needs antiarmor and antiaircraft weapons to shift the momentum on the ground to its side. He said if the administration gives him enough specifics about the new arms pledges, he’ll vote to authorize military action.

“For the first time we have an outline of action that could lead to the removal of Bashar al-Assad,” McCain said. “I’m certainly willing to join in that effort, but I need to know a lot of the details.”