Actress Angelina Jolie says her four-month-old twins are already developing their own characters.

The Tomb Raider star gave birth to Knox Leon and Vivienne Marcheline in Nice, France, in July, with partner Brad Pitt by her side.

And speaking at the DVD launch of Kung Fu Panda, the 33-year-old said the twins are growing fast.

"They're great. They're still so little, but they do [have their own personalities]," she told reporters in Hollywood on Sunday.

The babies are "starting to get very smiley," she added. "They're at that [stage] where their personality really starts to shine."

Jolie and Pitt are already parents to four children together: adopted children Maddox, six, four-year-old Pax Thien and Zahara, three, as well as biological daughter Shiloh, two.

And she confirmed she had twins on the way when her Kung Fu Panda co-star Jack Black let slip in May that Jolie and Pitt would be adding two more children to their brood.

Of Kung Fu Panda, in which she voices Tigress, one of the Furious Five kung fu sect, Jolie said: "I think it's a great film, and it's brought a lot of joy to children – and to my children, absolutely.

"My kids love it. They're very, very proud, they've got mom [Tigress] dolls."

Jolie and co-stars Black and Dustin Hoffman were also on hand as Dreamworks' president Jeffrey Katzenberg presented a check for $1 million (£636,740) to the Conservation International group to support its efforts to preserve pandas in their natural habitat.

10/11/2008 10:10:14