The plan, completed last week, envisions withdrawing two more brigades, or some 7,000 to 8,000 troops, from Iraq in the first six months of 2009, the military officials said. But that would leave 12 combat brigades in Iraq by June 2009, and while declining to be more specific, the officials made clear that the withdrawal of all combat forces under the generals’ recommendations would not come until some time after May 2010, Mr. Obama’s target…

Mr. Gates has expressed confidence that he and Mr. Obama might reach common ground. But in discussing the new plan, senior military officials nonetheless made clear that they were not comfortable with the time frame Mr. Obama articulated in the campaign. “Sixteen months is going to be tough,” said one senior military officer who was briefed on the plan. “We are not quite there yet.”