Empire Online spoke with Chris Carter and brought us the following:
Speaking of which, fans are eagerly awaiting news of a third movie. Have you anything to share?
"It's really up to Twentieth Century Fox, whether they have the will to do it. I think all of us are interested in putting the band back together. I have an idea for a third movie in my head. The colonisation date has passed [in the series, the date for the alien invasion was December 22, 2012 - Ed.] and that is something we wouldn't ignore. For the second movie, we only had the budget for a standalone story, but we want to go back to the mythology."