George Clooney has hailed Matt Damon as the "greatest actor" he has "ever" worked with.

Matt Damon

Matt Damon

The 56-year-old actor has praised his 'Ocean's Eleven' co-star as being the most talented star he has worked with and even "seen" in his entire life, and although the silver fox has racked his brain to think of a star better than the 46-year-old he can't think of anyone "better".

Speaking to 'Entertainment Tonight', the 'ER' heartthrob said: "Matt's the greatest actor I've ever worked with. In fact, I don't know a better actor I've seen in my life. I'm trying to think if there's a better actor. Nope, there's not a better actor. No, there is not."

The 'The Martian' star has also credited George for his professionalism in the entertainment industry, and believes George is "over prepared" for the projects he takes on, although he has hinted he wouldn't want his pal to be any other way.

Matt said: "It's not the first time I've worked with the wonderful and talented and brilliant George Clooney. He does things that other directors just can't do. He pays me in cash daily. You just don't see others doing that at this level. He's fantastic. I've done a bunch of movies with him as a producer, as a writer, as an actor, as a director and it's why I keep coming back. He's over-prepared."

Although George directs Matt in the crime film 'Suburbicon', it is the 'Jason Bourne' star who advises George on parenting.

The Kentucky-born filmmaker - who has two-month-old twins Alexander and Ella with his wife Amal - explained: "Now that I've got kids, Matt gives me direction.

"I'm a mess. But [Amal] is like an Olympic athlete. You've got two kids, you're breastfeeding like crazy. I'm very good, by the way, at diaper changing.

"This is an all-new adventure for me ... [Fatherhood] has made me much older. It doesn't fundamentally change you, but I'm excited to see who these two people are going to be in life. I'm very proud to be [a dad]. I feel honoured to be a part of it."

Although George is "honoured" to be a father, he never thought he'd be married with children.

He said: "Honestly, I didn't think I'd be married with two kids. The world changes! I love being here [in Venice, where he married Amal]. It's a magic, improbable city."