Slumdog Millionaire director Danny Boyle is to film the true story of an American climber who hacked off part of his arm with a knife after it became trapped under a rock, according to reports.

The award-winning filmmaker is confirming plans to direct 127 Hours, based on Aron Ralston's extraordinary ordeal in Utah's Blue John Canyon in 2003, US entertainment magazine Variety reported.

In a desperate bid for survival, Ralston used a blunt knife and pliers to amputate his right forearm after it was pinned between a boulder and the canyon wall for nearly five days.

The mountaineer documented his experience in a book entitled Between a Rock and a Hard Place. He has also appeared on US talk shows and is now a corporate speaker.

Production is due to begin in 2010, with the film scheduled for release late next year.

The movie will reunite Boyle with the creative team and financiers behind Slumdog Millionaire, a movie which won eight Oscars.