'X Factor' Finale: Avril Lavigne, Alanis Morissette, R. Kelly to Duet with Finalists

Avril Lavigne Publicity 2011

Judges LA Reid and Simon Cowell recruit music stars they discovered for the show's two-part finale. Also, Justin Bieber posts a finale hint on his Facebook page and Leona Lewis is set to sing Snow Patrol's "Run."

The final sing-off between X Factor contestants Melanie Amaro, Josh Krajcik and Chris Rene is hours away and up until late Tuesday night, negotiations were still ongoing for guest stars to appear on the two-part all-star finale airing Wednesday and Thursday on Fox. 

So who's on deck? Sources tell the Hollywood Reporter that Avril Lavigne will duet with Rene, Alanis Morissette will be paired with Krajcik and R. Kelly will sing with Amaro on Wednesday. Lavigne, viewers may recall, was signed by X Factor judge LA Reid to Arista Records in 2000 while she was still a teenager. Now 27, the pop-punk singer recently made a label switch to Sony-owned Epic Records so she can rejoin the Reid roster.

Leona Lewis, winner of season 3 of X Factor UK, is also set to perform on Thursday. An insider reveals that she will be singing her stellar cover of Snow Patrol's "Run." 

As previously reported, and confirmed by creator and head judge Simon Cowell at a Monday press conference, Justin Bieber will appear on Thursday’s show, performing with (spoiler alert) X Factor finalist Drew Ryniewicz (who auditioned with a slowed-down version of Bieber’s “Baby”) and the legendary Stevie Wonder. On Wednesday afternoon, Bieber took to Facebook to post a photo of himself with the music legend which was taken at Wonder's Toys for Tots benefit concert on Saturday night (see right). With it, Bieber wrote: "Such an honor. and this is a hint. Watch the X FACTOR FINALE on the 22nd."

Ne-Yo and Pitbull will also take the X Factor stage, and Cowell alluded to “two more performances” that had yet to be confirmed. “My gut feeling is it’s going to happen,” he told reporters, explaining that on Wednesday, each of the three finalists “are going to perform with a superstar artist and do a duet that will be part of the competition.” 

An X Factor representative declined to confirm any guest performers. 

Twitter: @shirleyhalperin