[cnn-photo-caption image= http://i2.cdn.turner.com/cnn/2008/images/07/27/art.mccain.gi.jpg
caption="Sens. John McCain and Barack Obama have been exchanging tough words about Iraq."]
(CNN) - With just 100 days until the election, Sens. John McCain and Barack Obama are accusing each other of shifting their positions when it comes to Iraq.
Obama accused McCain of altering his stance after the senator from Arizona said 16 months would be a "pretty good timetable" for troop withdrawal, and McCain said Obama was becoming more inline with his position - a "conditions-based" plan for withdrawal.
In an interview with Newsweek, Obama was asked about what sort of U.S. troop presence he would keep in Iraq, now that he has talked with diplomatic and military leaders there.
Obama returned to the United States on Saturday after spending more than a week in the Middle East and Europe.
"I do think that's entirely conditions-based. It's hard to anticipate where we may be six months from now, or a year from now, or a year and a half from now," he said in the interview, which was published on Saturday.
Obama has been a strong advocate of a 16-month timetable for withdrawal, while McCain has maintained that conditions on the ground must dictate plans for withdrawal.
In a statement issued Saturday, McCain's campaign said they welcomed Obama's shift to an "entirely conditions-based" withdrawal from Iraq.