Starry night for Roberts and Zeta Jones

Roberts and Zeta Jones: Warm greeting

Hollywood actresses Julia Roberts and Catherine Zeta Jones have added some glamour to the star-studded Los Angeles launch of their new film America's Sweethearts.

Oscar-winner Roberts plays an awkward, self-conscious Kiki, who works as the personal assistant to beautiful starlet Gwen, played by Zeta-Jones.

The movie, which also stars Billy Crystal and John Cusack, is a comedy telling the story of the break-up between two high-profile stars.

Billy Crystal joined the starry line-up

Roberts, who recently split from her actor boyfriend Benjamin Bratt, was originally asked to look at the part of Gwen, but said Kiki appealed to her more.

"The script was so funny and just seemed so kind of whimsical and farcical, but the thing that really stood out to me was Kiki, and what's this little secret girl all about," she said.

Welsh-born Zeta Jones, who was accompanied to the première by her husband Michael Douglas, said she had the "time of her life" playing Gwen.

"What I love about her is that she really does believe that she is like Mother Theresa, telling the world, you know, making the world happy, and she does have that persona," she said.

Zeta Jones was joined by husband Michael Douglas

"But when the doors close she just is the most self-obsessed woman you'll ever meet in your life."

This is not the first time Roberts has hit headlines in recent weeks - earlier this month she spoke publicly for the first time about her split from her long-term boyfriend Bratt.

Speaking as a guest on the David Letterman show in the US, Roberts, 33, said their four-year affair had come to a "tender-hearted end".

She also denied that the break-up had been caused by her rumoured "involvement" with former ER heart-throb George Clooney.