The weird hobby that fuelled Brad Pitt and Leo DiCaprio's bromance

Brad Pitt and Leonardo DiCaprio bonded over pottery.

The two Hollywood A-listers star together in Once Upon a Time in Hollywood, and since striking up a friendship on set, they've reportedly been spending time together indulging in their shared love for pottery, where they spend their evenings "creating art" at Brad's sculpting studio.

A source told The Sun newspaper's Bizarre column: "Brad's got his own sculpting studio at his house and Leo loves coming over to use it.

"They sometimes hang out with Brad's artist pals, but other times it's just the two of them.

"Leo brings sandwiches over from their favourite place, Fat Sal's, and they spend their boys' nights creating art until the early hours."

The news comes after Brad and Margot Robbie — who also stars in the Quentin Tarantino movie — poked fun at their co-star Leonardo for his role in Titanic, which Margot branded the "biggest controversy in modern cinema".

Leonardo plays Jack Dawson in the James Cameron flick, and his character's death has been the topic of discussion for decades, as he perishes in the icy waters while Kate Winslet's Rose DeWitt Bukater stays safe on a floating wooden door, which many believe Jack could have easily fitted on.

In an interview, the trio were asked: "Biggest cinema controversy of all time, could Jack have fit on that door?"

Suicide Squad star Margot immediately responded: "I thought it. I remember bawling my eyes out when I was a girl."

Leonardo quickly replied: "I have no comment."

Brad weighed in: "That is funny ... Well, I'm gonna go back and look now. Shoot!"

Margot joked: "That is the biggest controversy, I think, in modern cinema."

Brad then teased: "Could you, could you have squeezed there? You could've, couldn't you?"

Margot added: "Did you mention it at the time? Were you like, 'Should we make the door smaller?'"

Leonardo refused to comment but was chuckling, prompting Brad to reply: "It's movie magic my friend, movie magic."

- BANG! Showbiz