06/12/2007 at 08:00 AM EDT
and Cameron Diaz
reunited on Shrek the Third
's green carpet in London Monday.
The former couple greeted each other with a quick hug before going their separate ways to work the crowd that had gathered to celebrate the film's U.K. premiere.
What's it like working with her ex? "He's been great and we've been working so hard together to promote this film," Diaz, 34, told PEOPLE.
Of course, this wasn't the first time the two had appeared together at a Shrek
event: They shared a friendly kiss
at the film's L.A. premiere last month. And last week, they promoted the film together in Berlin.
The day before the London premiere, Diaz visited the famous Great Ormond Street Children's Hospital. "[The kids] are all so brave," she told PEOPLE. "They really make you thankful for your own health. They were wonderful."
On the green carpet, the Chanel-clad actress, who plays Princess Fiona in the film, and Timberlake (young prince Artie) were joined by castmates Rupert Everett (Prince Charming) and Antonio Banderas (Puss-in-Boots).
Banderas said that making a cat into a sex symbol wasn't too difficult: "It was remarkably easy actually, once you understand the method that is."