Michael Douglas has spoken of his pride in wife Catherine Zeta Jones, as she returns home after a stint in rehab.

The two-time Oscar winner, who was at the Cannes Film Festival for the premiere of his new film Behind The Candelebra, revealed the Welsh actress has completed her latest treatment for Bipolar II disorder and was returning home on Tuesday.

"She's doing a really good job of getting balanced. I'm proud of her," he told People.

The 68-year-old also told Extra: "She's raring to go!"

Catherine "proactively" checked into a treatment centre for the second time in April.

Michael, who has been winning praise for his portrayal of flamboyant entertainer Liberace in Steven Soderbergh's film alongside Matt Damon as his lover Scott Thorson, admitted that the actress is already a fan of his latest work.

"She loves it. It cracks her up. She thinks it's a great movie," he said.

The actor said it was a no-brainer to join the film.

"You've got to put it in perspective... Coming off of the cancer, I was just happy to be alive, and then someone hands me one of the best scripts I've ever read. Steven Soderbergh tells me he's going to direct, Jerry Weintraub is going to produce, Matt Damon is going to be my co-star and I get to play Liberace! I was like, 'Aw, baby this is too good to be true!' I was ready for some good luck," he said.

He added: "He (Liberace) was a very hard-working guy who never seemed to lose his cool. It was a joy playing a nice guy. I don't get to play a lot of nice guys."