Hugh Jackman has joked he ate nothing but "fried rocks" to get in shape for 'Deadpool and Wolverine'.

The 55-year-old actor reprised his role as the Marvel superhero to appear alongside Ryan Reynolds in the summer blockbuster - and Hugh has laughed off the lengths he went to buff up for the shoot.

During an appearance on 'The Tonight Show Starring Jimmy Fallon', the host asked: "You eat like steamed rocks or something. What do you have?" and Hugh replied: "Yeah, sometimes I fry the rocks."

The Hollywood star went on to reveal he ate a high-calorie diet, but it wasn't particularly exciting, explaining: "It’s 6,000 calories, and it’s not the calories you necessarily want. Like, half a pizza is 6,000 calories.

"But no, this is chicken, and it’s tilapia and beans. Tilapia and beans. I don’t know why tilapia. It must be some fish that is lean, and green beans."

Hugh also revealed he ended up staying on his gruelling diet for longer than expected after the movie shoot was delayed due to the Hollywood writers strike last year.

He added: "There’s one particular scene where I really wanted to focus on how I looked. And [director] Shawn [Levy] said, ‘Where do you want to do that scene?’ And I said, ‘Let’s just put it to the end.’

"And then the strike came, and I was like, ‘Oh, why did I say that ?'"

It comes after director Shawn Levy revealed Hugh gave him permission to include a joke about his divorce from Deborra-lee Furness in the new movie.

The film includes a gag referencing his personal life as well as that of co-star Jennifer Garner, who is divorced from Ben Affleck, and Shawn is adamant he'd never include those kind of jokes without the actors' permission.

He told Variety: "We never did a joke about or with anyone that we didn’t run by them first. Whether it was scripted, like the 'Daredevil' line, or unscripted, like 'He’s normally shirtless, but he’s let himself go since the divorce,' which was more of on-set improv, Ryan [Reynolds] or I would always run the lines by performers and make sure everyone felt comfortable and that we were never punching down."

Shawn confirmed that Hugh and Jennifer, 52, both "felt good" about including jokes about their failed marriages in the movie.

He added: "It was all in a playful spirit that everyone felt good about. Those lines wouldn’t be in the movie if Hugh and Jen didn’t think they were funny."