He is on the verge of taking the role of geneticist Aldrich Killian in the film, Variety reports.
In Warren Ellis's six-issue Iron Man: Extremis comics, the Killian character co-creates a powerful Extremis serum and releases it to terrorists.
The third instalment of the Iron Man series will shoot in Wilmington, North Carolina, with Kiss Kiss Bang Bang director Shane Black taking over from Jon Favreau.
Robert Downey Jr will again take the lead role of Tony Stark. It has been reported that Scarlett Johansson will return as Black Widow/Natasha Romanoff, who was an assistant to Stark in Iron Man 2, and that Sir Ben Kingsley is likely to play the role of the villain.
Mark Ruffalo has also suggested that he might appear in the guise of Bruce Banner.
Pearce will appear this summer as Peter Weyland in Prometheus, which is scheduled for release on June 1 in the UK and June 8 in the US.
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