George Clooney has called on young actors to ditch social media as he believes the sites diminish any ability to become "bigger than life".

During the latest episode of The Hollywood Reporter's Awards Chatter podcast, the Oscar-winning actor claimed casting directors and studio executives have asked him to select artists for his film projects based on their online following.

"When I was directing and I was casting, and it was between two actors, the casting director and the studio would come to me and go, 'Well, she's got 175,000 followers on Instagram, and the other girl's got 30,000.' Those were literally the discussions we had," he stated. "And I said to all these actors, 'Get the f**k off of it. Get off of all of it. Because if you're not on it, you have nothing to be compared to.'"

Clooney went on to note that he understands why actors are tempted to "monetise" social media to pursue other projects.

However, the Ocean's Eleven star argued that having a platform on sites like Instagram and Facebook won't benefit people's acting careers in the long run.

"But trying to maintain a career and answer all of the questions that every individual has for you, it's diminishing your ability to be bigger than life. It's inevitable, and I'm sort of swimming upstream, and I don't think that there's much you can do about it, but I do think it's better to not be as available," the 64-year-old continued.

Elsewhere in the chat, Clooney listed Zendaya and Glen Powell as two of the young stars he is most impressed by in Hollywood.

"I think Zendaya... can do television, she can do commercials, she can do movies, she seems to have that ability to rise above it," he smiled. "I think Glen Powell is doing interesting stuff as a young actor; he's kind of hitting around the time I hit, and he seems to want to direct and produce and write and do all of those things with a little bit of humour about himself, which I think is an element that's important if you look back."

Clooney is currently promoting his new movie, Jay Kelly.

Directed by Noah Baumbach, the drama is set to be released in select theatres on 14 November and have its global premiere via Netflix on 5 December.