(CNN) Comedian Sarah Silverman has said she was once fired from a movie after producers found a sketch from 2007 in which she wore blackface make-up.

In an episode of her former Comedy Central show "The Sarah Silverman Program" that she has said she no longer stands by, Silverman's character dons dark face paint to see whether it is more difficult to be black or Jewish.

The episode, which was intended to examine racism from the point of view of Silverman's eponymous character, features the comedian saying: "I look like the beautiful Queen Latifah," and telling the congregation at an African-American church: "I'm black today."

Speaking to the The Bill Simmons Podcast last week, Silverman revealed: "I recently was going to do a movie ... a really sweet part and a cool little movie."

"Then at 11 p.m. the night before, they fired me because they saw that picture of me in blackface from that episode," she added. "So they hired someone else who's wonderful but who's never stuck her neck out."

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