More secret details of Angelina Jolie's pregnancy have been exposed by a Kung Fu Panda co-star - Dustin Hoffman has revealed the actress is due to give birth to twins on August 19th.

Speaking at the Cannes Film Festival, in France on the same day Jack Black - another co-star in the animated movie - accidentally confirmed Jolie is expecting twins, Hoffman has disclosed more information about what has become Hollywood's worst-kept secret.

Today show's Natalie Morales reveals in an interview that has yet to be aired, Hoffman told her, "She is due on August 19th".

The babies will be Jolie's fifth and sixth children, and her second and third biological kids with partner Brad Pitt.

The couple has three adopted children, Maddox, Pax and Zahara, and their first natural child, Shiloh, will turn two this month.