"It's amazing how much work you can get done when the cameras aren’t around," he said. "We need to be careful about how ... we inject ourselves in this process."
He added: "There's still some work that needs to be done. ... Right now, there needs to be a sense of urgency on the part of everybody."
Obama said that there seemed to be broad agreement on a deal but that "something happened in the intervening hours" he was in the air.
He said he still intends to attend Friday's debate in Oxford, Miss., and urged McCain to do so.