Batman actor and director Ben Affleck has reiterated his desire to feature Sienna Miller in his upcoming Justice League spin-off movie, but is yet to reveal the exact role he has in mind.

The 44-year-old, who debuted as the caped crusader in last year's Batman V Superman: Dawn of Justice, spoke out about his plans while promoting new film Live By Night, which he directed and stars in alongside Miller.

When asked about the British actress' suitability for villain Vicki Vale, Affleck told HeyUGuys: She's perfect for anything. She could do anything. Vicki Vale's kind of bitchy, I think she's better for… well," before stopping himself and adding "we won't say that."

Journalist Erik Davis previously claimed Miller, 35, had expressed a desire to feature in the upcoming title.

"Sienna Miller told me tonight that she wants to play Catwoman in Affleck's Batman movie. She's not in the script but I wanna write her in!" he tweeted last year.

The film has no official release date or cast other than Affleck, Jeremy Irons (as Alfred Pennyworth), and Joe Manganiello (as Batman's nemesis and one-time mentor Deathstroke). It is being developed by Affleck and DC Chief Creative Officer Geoff Johns, report Comicbook.com.

The project is reportedly largely in flux, and Affleck has previously noted that he will not push the film until he is happy with its concept.

He previously told USA Today that changes will need to be made to the Batsuit for him to successfully fulfil his dual acting and directing duties.

"We'll have to modify the suit to make it a little bit easier to put on and take off," he said. "When you are in it, you can be sweating, crazy and exhausted, do your part and walk away. But when you're a director, you can't walk away. You have to be there for everybody. Chief among the challenges of doing Batman, will be finding a suit that's more comfortable."

The Batman solo project, currently without a release date, is among a slew of movies penned for release based on the DC Comics universe, due to be released between June this year and July 2020.

  • Wonder Woman – 2 June
  • Justice League – 17 November
  • Aquaman – 27 July 2018
  • Shazam – 5 April 2019
  • Justice League 2 – 14 June 2019
  • Cyborg – 3 April 2020
  • Green Lantern Corps – 24 July 2020.
Ben Affleck and Sienna Miller
Ben Affleck and Sienna Miller starring Live By Night releases on 13 JanuaryGetty