But Damon, who this summer bids farewell not just to Linus, the "Ocean's" burglar, but amnesiac Jason Bourne as well, kept his options open, saying he was "more sad" that he might not get to do another flick with the "Ocean's" posse.
"The Bourne thing I’m definitely done with," he added. "We've ridden that horse as much as we can. Outside of feeling like a prostitute for putting out two No. 3s in one year..."
"Better than three No. 2s," Clooney instantly noted to laughter.
Damon agreed. But does his vow to not be Bourne again mean that Jason dies?
"I'm not going to say. I could just not do them anymore," Damon said, adding that "the character lives on in the books," so another actor could be born as Bourne.
Matt Damon told me he has agreed to star in Paul Greengrass's movie about the chaos in Iraq.
The actor and director have been doing final post-production work on The Bourne Ultimatum and they clearly enjoy working together.
Greengrass, who was nominated for an Academy Award for his extraordinary work on United 93, will begin shooting a picture based on Rajiv Chandrasekaran's non-fiction book Imperial Life In The Emerald City, which explored the Americans' calamitous efforts to set up a provisional government in Baghdad, with people being hired more for their loyalty to President Bush than their qualifications.
"Paul's still working on The Bourne Ultimatum and the script for Emerald City isn't complete - but I think the idea is for a farcical tragedy," the actor said when we met at the Hotel du Cap.
Although the film will be based on Chandrasekaran's real-life accounts, Matt told me the character he would play would be fictional.
"They're creating someone for me to play based on several people - a sort of composite," he explained.
Filming on the movie, being produced by Tim Bevan and Eric Fellner from London's Working Title studio, begins in February.