After filming the sequels The Bourne Supremacy and The Bourne Ultimatum and the semi Bourne-y upcoming thriller Green Zone, you couldn't blame director Paul Greengrass for needing a change of pace. Amid rumors that he and Matt Damon would re-team for a fourth Bourne film, Greengrass effectively squashed the possibility that he'd return to the franchise that made his Hollywood career back in December. Doing press for his latest film this week, he set the record straight about his change of heart.

In an interview Friday with CHUD's Devin Faraci, Greengrass explained why he had become burned out on Bourne and what his quitting the franchise meant for his relationships with its studio and star. Despite his decision against continuing with the franchise, he thinks another sequel could be made -- just without him at the helm.

"I didn't have the fire in my belly," Greengrass told CHUD of the potential fourth film in the series. "Not that I don't like Jason Bourne, not that I'm not extremely grateful to the franchise, not that I'm extremely close to the studio - there were no arguments. I didn't feel like I had anything else to contribute. It just happens with franchises; you get to a point where you feel like you've done it." (Read more here.)

Greengrass emphasized that his decision didn't affect his working relationship with Bourne star Matt Damon, with whom he reteamed for his March war film, Green Zone. That action drama, based on the 2006 non-fiction book Imperial Life in the Emerald City, stars Damon as an Army specialist searching for weapons of mass destruction in Iraq who is possessed of some serious hand-to-hand combat skills and goes rogue amidst a conspiracy, a la Jason Bourne.

It's clear that Greengrass doesn't want to stop making interesting action films -- he told CHUD he wants to do a "fun and new" action pic next -- and that he intends to keep his successful working relationships intact. He's just tired of the Bourne universe. (And really, aren't we?) Kudos to him for opting for new challenges over the easy sequel cash-ins -- even if his post-Bourne projects feel more than a little bit familiar.

Watch the trailer for Green Zone below and tell us if you think Greengrass made the right decision. Moreover, who do you think should step into the director's chair to resume the Bourne franchise? And if he keeps making shaky-cam espionage movies with Matt Damon, don't they practically count as unofficial Bourne sequels?