"Most of Angelina's tattoos are pretty discreet but these map coordinates really stand out," said a festival onlooker. "When she made her way up the red carpet, she kept her arm hidden behind Brad, and looked really elegant in a demure black dress and peep toe heels.

On the red carpet: Angelina Jolie and Brad Pitt arrive at the world premiere of 'A Mighty Heart' in Cannes

The latest tattoo is understood to be Miss Jolie's 13th to date.

She already has a discreet M on the palm of her hand - a tribute to her mother, Marcheline Bertrand, who died earlier this year.

On top of this, she has a Buddhist Pali prayer written in the Khmer script for Maddox as well as a Tennessee Williams quote, "A prayer for the wild at heart kept in cages".

Angelina Jolie's new tattoos have been inscribed in the same spot where a tribute to her ex-husband Billy Bob Thronton once lay.

His name was tattooed onto her left arm along with a Chinese dragon - the remnants of which are still faintly visible even after laser removal surgery.

She said at the time of the laser treatment: "I'll never be stupid enough to have a man's name tattooed on me again."