Christina Aguilera is working on her "best album yet".
The 'Candyman' singer has collaborated with M.I.A., Flo Rida, Le Tigre and Santigold on LP 'Light and Darkness', which is being produced by Tricky Stewart, the mastermind behind Rihanna's 'Umbrella' and Beyonce Knowles' 'Single Ladies'.
Tricky said: "It's just great. I wouldn't say that it's alternative, I wouldn't say that it's different. Christina's always been an artist that moves the bar and that's what the great ones do.
"They don't stay in the same place for too long and this album is just another move for her. I really feel it's one of her best bodies of work that I've heard since 'Stripped'."
The LP will be Christina's fourth studio album, and her first since 2006.
But although the album is almost finished, it won't be released until next year because Christina is too busy working on new film 'Burlesque' with Cher.
Tricky added: "She's gonna do the film first. She didn't want to not be able to promote this record because it's going to be a big record for her.
"The album is finished. She's mixing. She hasn't made a final decision about what the first single is, but I know everyone feels good about their options."