Exclusive: Inside Christina Aguilera's AMA Performance!

Christina Aguilera arrives at the NBC's 'The Voice' Season 3 at House of Blues Sunset Strip on November 8, 2012 -- Getty Premium

Christina Aguilera is hard at work rehearsing for her big performance at the 2012 American Music Awards on Sunday - and Access Hollywood has the exclusive details on what the pop diva will perform.

The superstar singer will treat fans to a medley of new songs off of her latest album, "Lotus," including, "Let There Be Love," "Army of Me" and "Lotus," a source inside Christina's closed AMA rehearsal revealed to Access on Saturday.

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"The Voice" coach will begin her performance in a pink dress, before vanishing for about one minute in, then reemerging rocking a glittering black bustier.

Christina's performance will feature an anti-bullying theme, the source said, with her dancers dressed as misfits (including bikers, drag queens, etc.), and carrying signs featuring words associated with bullying, such as "doubt," "hate" and "fear."

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Catch Christina's performance (along with performances by Psy, Carly Rae Jespen, Kelly Clarkson, The Wanted and more) on the 2012 American Music Awards - Sunday at 8/7c on ABC.

-- Erin O'Sullivan

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