Joaquin Phoenix was told he was being "unprofessional" by Russell Crowe on the set of 'Gladiator'

Filmmaker Ridley, 86, who has just released 'Gladiator II' starring Paul Mescal, told the New York Times: "(Joaquin) was in his prince's outfit saying, 'I can't do it'.

"I said, 'What?' And Russell said, 'This is terribly unprofessional'."

Ridley added about how he also coaxed Joaquin to stay in the job: "I can act as a big brother or dad. But I'm quite a friend of Joaquin's.

"'Gladiator' was a baptism of fire for both of us in the beginning."

The film ended up winning five Oscars, including best picture.

Joaquin recently said one of his favourite things on set is a lack of ego.

He gushed Lady Gaga, 38, who was his co-star on 'Joker: Foile À Deux', displayed no diva tendencies when they were working together.

The actor said in a behind-the-scenes featurette film put out ahead of the 'Joker' sequel's cinema release: "I found (Gaga) to be without ego and had such a fierce determination. She would get right in with us.

"She understood that there had to be a rawness to the character. There's not a lot of actors that are comfortable working in that way."

Gaga also spoke in the featurette, and said about making the 'Joker' follow-up: "It was a very special experience. I had never seen a world created like that before."

"It brought out all of that rough and tough energy and how big these dreams were, and how far they would fall."