Cameron Diaz gave Katzenberg her blessing to cast Justin Timberlake

Movie boss Jeffrey Katzenberg sought Cameron Diaz's blessing before casting her then-boyfriend Justin Timberlake in his new film 'Shrek The Third'.

The Dreamworks chief was worried Diaz, who split from Timberlake in December, would balk at the idea of mixing her personal and professional lives.

But he was pleasantly surprised by how open Diaz, who voices Princess Fiona in the animated franchise, was to casting Timberlake as the voice of Artie.

Katzenberg says: "Out of courtesy, I said to Cameron, 'You know, this is something we're considering doing. I like this guy's work a lot. On the other hand, I don't want to mix things up here. Life is already confusing enough for all of us.'

"She was completely supportive: 'If that's something you want to do, then great. Obviously I'm a fan and admirer, too.'"