French actress Marion Cotillard has vowed never to return to a sea-life centre after shooting scenes for her new film role as an Orca trainer at a water park.

The Oscar winner, who is a Greenpeace activist, admits the work she had to do for Rust & Bone at a Maryland Sea World made her sick.

She tells C magazine, "I'd rather see whales in their own environment and not in a swimming pool. I will never go back to a Sea World."

Cotillard adds, "I really feel uncomfortable in these places, where animals are kept in captivity, so when I got there, I was really anxious, but then I had to do the job and I met these people who are passionate about what they do. I respect them but I will never understand."