Sienna Miller has praised late Hollywood star Chadwick Boseman for donating part of his own salary to boost her pay packet on 21 Bridges.

The pair starred as detectives in the thriller, which was released last year.

Miller told Empire: "Everybody understands about the pay disparity in Hollywood, but I asked for a number that the studio wouldn't get to.

"And Chadwick ended up donating some of his salary to get me to the number I had asked for."

She added: "He said that that was what I deserved to be paid."

Black Panther star Boseman, who died of cancer earlier this year, was also one of the film's producers and had pursued Miller for the role of Frankie Burns.

"He was a fan of my work, which was thrilling, because it was reciprocated from me to him, tenfold.

"So he approached me to do it, he offered me this film, and it was at a time when I really didn't want to work anymore. I'd been working non-stop and I was exhausted, but then I wanted to work with him.

"And because I was hesitant to go back to work and my daughter was starting school and it was an inconvenient time, I said, 'I'll do it if I'm compensated in the right way.'"

Miller said Boseman's action was unheard of in the film industry.

"It was about the most astounding thing that I've experienced," she said.

"That kind of thing just doesn't happen. He said, 'You're getting paid what you deserve, and what you're worth.' It's just unfathomable to imagine another man in that town behaving that graciously or respectfully.

"In the aftermath of this I've told other male actor friends of mine that story and they all go very, very quiet and go home and probably have to sit and think about things for a while. But there was no showiness, it was, 'Of course I'll get you to that number, because that's what you should be paid.'"

Miller said she wasn't sure whether to tell the story at first but then decided she would "because I think it's a testament to who he was".

The interview appears in a special commemorative issue of Empire Magazine. Journalist Alex Godfrey, who spoke to Miller, noted on Twitter that "this is a story she particularly wanted to tell".