The 33-year-old comedian - who won a prestigious Tony award for Best Performance by an Actor in 'One Man Two Guvnors' on Sunday (10.06.12) - has been cast as tenor Paul Potts in Harvey Weinstein's biopic about the opera singer's difficult rise to fame.
Harvey told the Daily Mail newspaper: ''James is a brilliant actor and a wonderful comedian and we're excited to be working with him - and David - on this inspiring true story.
''Hot off James's Tony win, we can't wait to get started.''
Paul worked as a mobile phone salesman before winning the first series of Simon Cowell's TV talent show 'Britain's Got Talent' in 2007.
'Gavin and Stacey' funnyman James will work on the screenplay with director David Frankel.
'Part of Me' singer Katy Perry is reportedly in talks to play his wife, Julie-Ann Cooper.
Harvey previously said: ''I was talking to Katy about a new project, a possible dramatic role in the Paul Potts movie, which will be shooting in England soon.
''We'd really like someone like Katy or Adele to play the role of Potts' wife, and Katy seemed genuinely interested.''
Filming will begin in October.