Emma Thompson reveals she almost quit a movie after a producer asked her costar to lose weight

Emma Thompson isn't afraid to speak up for her fellow actresses.

The 57-year-old British star recently appeared on Swedish talk show Skavlan, where she revealed she threatened to quit the 2008 film, Brideshead Revisited, after a producer asked her co-star to lose weight.

"There was a wonderful actress I was working with in a film I did called Brideshead Revisited," she recalled. "And the producer said to her, 'Will you lose some weight?' And she was absolutely exquisite!"

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"I said to them, 'If you speak to her about this again, on any level, I will leave this picture. You are never to do that,'" she continued. "It's evil what's happening out there, and it's getting worse."

See photos from the premiere of Emma Thompson's latest film, "Beauty and the Beast":

Thompson also talked about the issue of anorexia.

"There are so many kids -- girls and boys now, and actresses who are very, very thin, who are into their 30s -- [who] simply don't eat. They don't eat."

"Sorry, do you want me to be an actress or a model?" she also quipped at one point.

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In January, 28-year-old actress Lily Collins opened up about her struggle with eating disorders as a teenager, and talked to ET about playing a woman battling anorexia in her film, To the Bone.

Watch below: