Anna Paquin, the American actress, has announced she is bisexual.

The True Blood actress, who is engaged to her male co-star Stephen Moyer, recorded an ad for the the True Colors Fund, a non-profit organisation founded by Cyndi Lauper to support the LGBT community.

In it, she says: “I’m bisexual and I give a damn.”

Paquin, 27, has never mentioned her sexuality publicly before.

The campaign is called Give a Damn and other celebrity supporters include Whoopi Goldberg, Elton John, Cynthia Nixon, Sharon and Kelly Osbourne, Kim Kardashian, Clay Aiken, and Wanda Sykes.

Goldberg has been a strong advocate of gay rights for years. Aside from a few cryptic remarks, such as saying in 2002 that she used to play “on both sides of the street”, she has maintained she is heterosexual despite rumours.