Thornton: 'I'm so happy for Angelina'

Billy Bob Thornton has congratulated ex-wife Angelina Jolie following news of her pregnancy.

Jolie's Kung Fu Panda co-star Jack Black confirmed last week that the actress is expecting twins with partner Brad Pitt.

She and Thornton adopted Cambodian orphan Maddox before divorcing in 2003 after three years of marriage. Maddox was later legally adopted by Pitt.

Thornton told OK!: "I think she was always meant to be a mother in so many ways. I'm just so happy for her. I'm happy for the kids to have a mother like her and a father like him."

The actor, who has been married five times, added that he was amazed by his former wife's work as a UN Goodwill Ambassador.

He said: "I'm astounded that somebody has that kind of passion and that much energy for something that actually does affect people and help people out."

Dustin Hoffman recently revealed that Jolie is due to give birth on August 19.