Screen reports that Pudsey: The Movie is set to star the winning duo, with shooting starting this spring.
Pudsey's manager Jonathan Shalit said: "This represents a hugely exciting next step."
Cowell's Syco Entertainment, responsible for TV formats such as The X Factor and Britain's Got Talent, will co-produce the movie with Vertigo Films.
Vertigo has previously created StreetDance: 3D, which starred Britain's Got Talent contestants Diversity and George Samson.
Global commercial director for Syco Mark Brittain said: "This is a really exciting initiative for us - and we look forward to working with Vertigo as it develops."
Rupert Preston from Vertigo said: "We're delighted to be developing this idea with Syco and we can't wait to bring Pudsey to the big screen."
The film is set to have a Christmas 2013 release.
Watch Digital Spy chat to Ashleigh and Pudsey below: