UPDATE: E! Online‘s Marc Malkin talked to Betty White last night who said she will NOT be appearing in the movie.
Betty White, best known as one of the stars of "The Golden Girls" has recently had a tremendous surge in popularity, starring in films like The Proposal and You Again. Scherzinger, meanwhile, is best known as the lead singer of The Pussycat Dolls.
E! confirmed the casting with Scherzinger herself, who told the outlet that she will play a woman named Lilly.
"She’s like a small villain role," said Scherzinger, "I’m so excited because I get to die. I make an appearance. I say a couple of lines and then I die."
Though White’s role is not named at this time, she will join the franchise returning stars, Will Smith and Tommy Lee Jones, as well as newcomers Josh Brolin, Jemaine Clement, Emma Thompson and Alec Baldwin.
Men in Black III is expected to go into production shortly with a script from Etan Cohen and David Koepp. Barry Sonnenfeld will return to the franchise as director. The film is being planned for release on May 25th, 2012.