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Raising eyebrows: Christina Aguilera puts on a provocative display as performs Express from her new film Burlesque on the X Factor last night
It's one of the biggest TV events of the year, watched by around a third of the British population.
But as the X Factor final kicked off last night, the talent show was accused of straying somewhat from its family viewing credentials as Christina Aguilera and Rihanna put on two extremely provocative pre-watershed performances.
Aguilera wore an extremely low-cut black dress as she cavorted with an army of lingerie-clad dancers while Rihanna thrust her way through her solo performance in pants and strapless bra.
Pre-watershed: Rihanna also set temperatures racing as she stripped down to fishnets, pants and a strapless bra. The performances from the two singers prompted a flood of outraged viewers to take to Twitter
The superstars jetted in from the States to appear on the show, with Aguilera duetting with Rebecca Ferguson and Rihanna supporting Matt Cardle.
But it was as they took to the stage for their second respective performances of the night - before the 9pm watershed - that they raised eyebrows, leading to Twitter being flooded with comments from outraged viewers.
Christina's rendition of Express from her new film Burlesque caused the most upset, with viewer left shocked as she did the bump and grind with her female dancers.
Family viewing? Christina sang lyrics including 'show a little leg, shimmy your chest'
Inappropriate: Her backing dancer, dressed in stockings, suspenders and lingerie, thrust themselves against their chairs
'Is it me, or is anyone else shocked at the raunchy performance from Christina Aguilera, being shown before the watershed?' tweeted Sallywoodings.
LottieLovesEwe was similarly taken aback:'Rihanna not so bad but Christina's was just wrong for 8.30 TV!! seriously inappropriate.'
Predicting scores of complaints another Twitter user, WhatsAboutTown, posted the message: 'OMG Christina Aguilera shocking..........how many complaints will ITV get about #xfactor tonight.'
The Sex Factor: Christina donned knee-high boots and a very low-cut black dress
Leaving little to the imagination: It didn't take long for Rihanna to whip off her black and white striped dressing gown and flash the flesh
Another, from x_tinamurhill, read: 'Rihanna and Christina's performance on #TheXFactor were very inappropriate in terms of clothing and dancing. It's a family show.'
Meanwhile dktom took to Twitter to accuse the two superstars of trying to out do each other with the raunch factor: 'I think Christina and Rihanna are trying to out-inappropriate each other. Crikey #xfactor brought me out in a sweat.'
Rihanna was performing her new hit What's My Name having earlier taken to the stage with Cardle to duet on her her Unfaithful number.
Double act: Rebecca was joined on stage by Aguilera earlier in the night as they performed a duet of Beautiful
Getting on like a house on fire: Rihanna and Matt performed her hit Unfaithful
Meanwhile Christina leant her support to Rebecca as they sang her hit Beautiful together.
The show was expected to receive around 21million viewers. After Cher Lloyd's exit tonight Matt, Rebecca and One Direction will battle it out in the grand finale tomorrow in a bid to win the X Factor crown.
ITV were unavailable for comment last night.
Source:Dailymail