Los Angeles: Singers Katy Perry and Britney Spears` voice will be heard in one song in the forthcoming movie `Smurfs 2`.
The song "Ooh la la" is sung by Spears and written by Bonnie McKee. Perry`s vocals are in the background, reports eonline.com.
"Me and Bonnie secretly did some background vocals on that song. So maybe listen for our voices," Perry said at the movie`s premiere here.
However, Perry hasn`t had a chance to meet Spears in person, and said: "I can`t wait to meet her."