Big Picture News Inc. reports that the Rolling Stones guitarist got the role due to his friendship with Depp and will join him and the rest of the cast in August for the filming of the movie's final scenes.
"We're friends. I thought about having Keith come on as my father when we did the first 'Pirates' film," Depp said. "It would be fun and interesting. I didn't realize this could actually happen. I hope he will play my dad in the third one. That would be fantastic."
Richards' recent injury -- falling out of a palm tree -- which has forced the Stones to cancel concert dates, but would not have any bearing on his role in the film, the news agency said.
"As long as Keith doesn't fall out of any more trees, it will be fine." producer Jerry Bruckheimer said.
The trilogy's second film, "Dead Man's Chest," is due out in theaters on July 7, while the third film featuring Richards' parental role is set to be released in 2007.