Ben Affleck is doing fantastic: Matt Damon

Matt Damon and Ben Affleck

Los Angeles: Actor Matt Damon says his friend and actor-filmmaker Ben Affleck is doing "fantastic" after he went to a rehabilitation centre for alcohol addiction earlier this year.

Damon says Affleck is busy looking after his three children - daughters Violet Anne and Sera and son Sam - as his estranged wife Jennifer Garner is tied up with work.

"He's fantastic… He's with the kids now, couldn't be happier. Jen's working for a couple weeks in Atlanta, so he's 'Mr Mom-ing' it right now. And that's what he wants to be doing," Damon told etonline.com.

Affleck revealed earlier this month on social media that he had undergone treatment for alcohol addiction so he can focus on being the "best father he can be" to his children.