Kelly Osbourne and Christina Aguilera have never liked each other

Kelly Osbourne reignited her feud with Christina Aguilera this week when she mocked the singer's weight on American television.

The pair have never got on, so when Kelly was shown an unflattering photo of Christina, 30, on channel E!'s Fashion Police, she took the opportunity to say her piece.

'Maybe she's just becoming the fat bitch she was always born to be,' Kelly, 26, told the show's shocked audience.

'I don't know. She was a c*nt to me.

'She called me fat for so many f*cking years, so you know what? F*ck you, you're fat too.'

Last month Kelly was embroiled in a Twitter war with ex-boyfriend Luke Worrall, 23, after he made vicious comments about her size while she was at good friend Amy Winehouse's funeral.

'You've made it very clear u only dated me 4 my life style but shit tweets about me the day im @ a funeral u have hit a new low,' Kelly, 26, Tweeted.  

'It was fine when my Kellyphant ass was paying 4everything wasn't it? i just didn't think u could get much lower but u did #wow.'

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