Naomi Watts' upcoming movie about tragic British royal Diana, Princess Of Wales has been edited to remove scenes featuring her two sons Prince William and Prince Harry.

The actress plays the title role in new film Diana, which focuses on the last few years of the princess' life before her death in a car crash in Paris, France in 1997.

The movie is due to hit cinemas in September (13), and it has now emerged director Oliver Hirschbiegel has made some major changes prior to its release, including cutting scenes featuring the two young princes.

The brothers, played by actors Laurence Belcher (William) and Harry Holland (Harry), will now only feature in one small scene, saying goodbye to their mother for the last time before her doomed trip to Paris, according to Britain's Daily Mail.

Hirschbiegel reveals the other scenes featuring the princes were dropped because "it never felt right to have them in the film".

He adds, "Everyone knew she was a brilliant mother and loved her boys to death."