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HEATED rows, sneering digs and bitter rivalries seem par for the course for pop stars these days.
She asked David Letterman: What is her song? Rolling In The Deep? She should add Fried Chicken.
Wars of words between competing stars have been raging for years.
Here are 10 of the most memorable celebrity spats in recent memory.
CHERYL COLE V CHER LLOYD
X spat-tor ... Cheryl Cole and Cher Lloyd
Cheryl was one of Chers most vocal champions during the mouthy singers stint on the X Factor in 2010.
However, relations between the girls turned sour when Cher accused Cheryl of relying on Auto-Tune during her live performances.
Asked last year if shed consider singing a duet with her former mentor, Cher replied: Maybe, if she sings live with me... its always a challenge nowadays when you havent got the nifty little button to press.
Cheryl was quick to react, writing on Twitter: Be Careful who you kick on your way up. They kick you twice as hard on your way back down. #unappreciationisugly.
In a later interview, the Girls Aloud star branded Chers attack as a slap in the face and revealed: She's new. She needs to learn a l! ot.
I went through hell to get her on that programme. Even with Simon. Everyone says stuff at the beginning of their career that they will learn to regret.
LILY ALLEN V CHERYL COLE
Love-hate relationship ... Lily Allen and Cheryl Cole
Cheryl made an enemy of Lily in 2007 after she called the Smile singer a chick with a d***.
Their rift appeared to be over by 2010, when Cheryl publically congratulated Lily on her ridiculously cute pregnancy snaps.
Two years later, Lily reignited the feud on Twitter when she commented on Sarah Hardings reported row with her then-boyfriend.
Aiming a dig at Cheryls 2003 criminal charge for abusing a toilet attendant in a nightclub, Lily tweeted: Wow 40% of Girls Aloud will have been charged with assault.
Cheryl responded by unfollowing her nemesis on Twitter.
Lily subsequently rubbished claims she had an irrational hatred of Girls Aloud by insisting their song The Promise was one of her favourite tunes.
NICKI MINAJ V MARIAH CAREY
American I-brawl ... Mariah Carey and Nicki Minaj
Rex
Rumours of rivalry between Nicki and Mariah surfaced before the outspoken stars had even sat down to judge wannabe pop stars on American Idol.
And it didnt take long for an explosive encounter to erupt, coming to blows when a disagreement over a contestants performance prompted Nicki to launch a foul-mouthed tirade at her fellow judge.
In video footage, Nicki was heard yelling: I told them I'm not f****** putting up with her f****** highness over there.
The rapper also allegedly told Mariah: Im gonna knock you out.
Such was the ferocity of the bust-up, producers were reportedly forced to cut auditi! ons short! in Charlotte, North Carolina, so the feisty divas could calm down.
TULISA V LORD SUGAR
Appren-tiff ... Tulisa and Lord Sugar
Lord Sugar incurred the wrath of Tulisa Contostavlos when he questioned her X Factor judging credentials.
He fired off several tweets, blasting the N-Dubz stars role on the show.
The Apprentice boss said: Can you tell me who the hell this Tulisa bird is what has she done?
This Tulisa talks nonsense on X factor, what qualifications does she have to judge singing talent.
Please advise where I am missing the point.
True to form, sharp-tongued Tulisa was quick to hit back and she didnt mince her words.
She ranted: As someone that came from nothing to something maybe u should have a little more respect for people that have done the same.
I have grafted from the age of 11 with my band NDUBZ, we wrote & produced all our music, sold 3 platinum albums, 3 sell out tours the last being an arena tour & a number 1 debut solo single!
I have worked my bloody ass off! So mr lord of judgement... stick to judging on the Apprentice & Ill stick to what I know MUSIC #itsaNOfromme.
Unconvinced by her argument, Lord Sugar responded: What do you know? That is the point. Dont insult me by comparing my humble beginnings with yours.
RITA ORA V ROB KARDASHIAN
Bitter split ... Rob Kardashian and Rita Ora
High-profile love splits can also give rise to public enragement as UK chart-topper Rita found out.
Her break-up with Rob turned very nasty indeed, with the brother of US reality TV star Kim accusing the singer of rampantly sleeping around during their relationship.
Following their separat! ion last ! year, he tweeted: She cheated on me with nearly 20 dudes while we were together, I wonder how many she will sleep with now that we apart? But I mean 20?!!!
How can a woman who is so busy trying to start her own career have time to be with so many dudes while in a relationship?!
Rita didnt hold back with her response, mocking the size of Robs manhood.
She wrote: Robs d*** was wack, I had to go get it somewhere else.
Rob retaliated, saying: So you let me get you pregnant and you let others hit raw?
A reunion is unlikely to be on the Kards...
ONE DIRECTION V PIERS MORGAN
One Dir-friction ... Piers Morgan and One Direction
David Beckham was unwittingly at the centre of Piers online dispute with One Direction.
It all started when Piers blasted Becks prospective transfer from LA Galaxy to another club, advising the footie icon to hang up his boots.
He wrote: No serious top-flight team would sign Beckham for football reasons any more he should retire gracefully.
Harry Styles was the first to respond, backing his footballing hero.
Louis Tomlinson followed, tweeting: I LOVE David Beckham!
Piers replied: Well sign him up for the group bet he sings better than he plays now.
Cant believe Im currently being sledged about Beckham by TWO members of One Direction. Boy-band types clearly stick together."
Harry called on mutual friend Simon Cowell to intervene, writing: Hiiii @SimonCowell can you tell @piersmorgan to leave us alone please? Hes being nasty.
Piers then declared war on the group before diffusing their online altercation possibly thanks to the 25 million One Directioners abusing him.
He tweeted: Lets settle this on my CNN show when you come to New York if youre brave enough.
Liam Payne responded: No hard feelings stinky.
ELTON JOHN V MADON! NA
Long-standing feud ... Elton John and Madonna
One things for certain Elton John is not a fan of Madonna.
The outspoken Rocket Man has repeatedly fired fury at the Queen Of Pop, last year branding her a fairground stripper whose career is over in a furious attack.
He added: Shes such a nightmare. Her tour has been a disaster and it couldn't happen to a bigger c***.
Earlier last year, Eltons partner David Furnish was equally venomous when Madonna won the Golden Globe for Best Original Song.
Her tune Masterpiece from her directorial debut movie W.E. beat Eltons Hello, Hello duet with Lady Gaga from animated flick Gnomeo & Juliet.
He vented on Twitter: Madonna. Best song???? F*** off!!! Madonna winning Best Original Song truly shows how these awards have nothing to do with merit.
Her acceptance speech was embarrassing in its narcissism.
In 2002, Elton described Madonnas theme song for 007 movie Die Another Day as the worst Bond tune ever.
Two years later, the singer famously slammed Madonna at the Q Awards after she was nominated for the Best Live Act prize.
Since when has lip-synching been live? Anyone who lip-synchs in public on stage when you pay 75 pounds to see them should be shot. Thank you very much.
That's me off her Christmas card list, but do I give a toss? No.
Madonna has largely kept silent, bar for occasional praise for Elton in an effort to downplay their spat.
GEORGE MICHAEL V ELTON JOHN
Taking the Michael ... George Michael and Elton John
Madonna isnt the only star to be lashed by Eltons scathing tongue.
Eight years ago, Elton went public with his fears for Georges wellbeing.
He claimed the f! ormer Wha! m! star was in a strange place, revealed the singer had a deep-rooted unhappiness in his life and described his solo album Patience as disappointing.
George who went on to crash his car into a Snappy Snaps shop while under the influence of drugs in 2010 wasnt best pleased.
He fired back: Elton John knows very little about George Michael and thats a fact.
Most of what Elton knows about my life is limited to the gossip he hears on the gay grapevine.
"He will not be happy until I bang on his door in the middle of the night saying, Please, please, help me, Elton. Take me to rehab.
Its not going to happen... Elton just needs to shut his mouth and get on with his own life.
However, peace was restored in 2011 when the pair apparently ended their quarrel.
A source said: They have been seeing each other quite a lot. The feud is finally over.
George and Elton are getting on brilliantly again and everybody is thrilled.
MADONNA V LADY GAGA
Scorn this way ... Madonna and Lady Gaga
The warring pop titans first clashed over the release of Gagas 2011 single Born This Way which bore a striking resemblance to Madonnas 1989 hit Express Yourself.
Initially, Madonna appeared to give Gaga her blessing after the tune hit the airwaves.
Gaga revealed the Queen of Pops camp had reached out to her sending me their love and complete support on behalf of the single.
She added: If the queen says it shall be, then it shall be.
However, Madonna subsequently proceeded to make a series of digs at Gaga hinting that her rival has been copying her.
In January last year, the Material Girl said Gaga references me a lot in her work and sometimes I think its amusing and flattering and well done.
Theres a lot of ways to look at it. I cant really be annoyed by it because, obviously, Ive influenced her.
Mad! onna fanned the flames during a gig in September, telling her audience: I love her. I love her. I do love her. Imitation is the highest form of flattery.
Although Gaga hasnt risen to the bait, she sent a clear message to Madonna in November when she snubbed the chance of performing onstage with her nemesis.
At a concert in Minnesota, Madonna revealed: I invited her onstage to sing with me. But she turned me down.
NOEL GALLAGHER & ROBBIE WILLIAMS
Take That ... Noel Gallagher and Robbie Williams
Robbie made a beeline for Oasis after quitting Take That in 1995, hanging out with the defunct Manc rockers at every given opportunity.
But his friendship with Noel and Liam didnt last long, courtesy of the guitarists scathing remark about Robbies portliness.
He famously called the former boybander the fat dancer from Take That.
After Robbie re-joined Take That, he boasted about the groups eight-date residency at Wembley Stadium in 2011 and insulted Noel in the process.
He said: The Rolling Stones have done two nights here.
Oasis did three - Take That are here for eight on the trot. Mick Jagger can lick Gary Barlow's face.
Noel Gallagher can lick my a***.
Never one to shy away from conflict, witty Noel responded: Lick his big fat Bobby Butlins a***?
Wow! The hormone replacements must be doing the trick, eh? I'd rather suck on his man boobs.