The British-born actress will portray Diana in Ecosse Films' upcoming biopic, simply called "Diana."Read more: Naomi Watts to play Princess Diana in biopic
Previously titled "Caught in Flight," the movie is being directed by Oliver Hirschbiegel and will star Naveen Andrews, Douglas Hodge and Juliet Stevenson.
The production company released a statement saying the film "charts how finding true personal happiness allowed her to achieve her defining successes, as she evolved into a major international campaigner and humanitarian."
Principal photography started this week. According to BBC News, Watts said from the set, "I'm excited and honored to be playing the role of a truly remarkable woman, who had such a positive and profound impact in so many ways."
The 43-year-old actress is six years older than Diana was when she died.
There's no official release date yet for "Diana," though it's expected out in 2013.
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