As of now, the project is still in development and there isn’t a script or expected release date.
Affleck and Damon's production company, Pearl Street Films, will produce the film, according to Deadline, who was first to report the news.
The project marks the first time the actors will work together since 1999's Dogma.The longtime friends first collaborated on Good Will Hunting in 1997, which won them Oscars for Best Original Screenplay. Robin Williams also received an Academy Award for Best Actor in a Supporting Role for his performance in the film. Damon later made a small appearance in Affleck's 2004 film, Jersey Girl.
Last year, Affleck opened up to ET about how much he values Damon's friendship and how he's been by his side for most of his life.
"I can't tell you how valuable it is to have somebody who's been through things with you, ups and downs, who knows what your life experience is like, who can identify with that," Affleck told ET. "It's an incredibly valuable friendship and it's very precious and so is my friendship with my brother. I don't know what I would do without those guys."