The 2007 'King of the Jungle' slammed McKeith for "ruining" this year's series by declining to take part in bushtucker trials and sulking around the camp.
He told The Sun: "She refuses to do anything, and if she cannot do it she should get out. She has a huge ego and probably thinks she's being picked for the tasks because she's so popular, the poor, deluded woman.
"She must be the most obnoxious, selfish, vindictive woman I've ever had the misfortune to watch on TV. She's ruining the programme. My advice to her would be to try harder and be kinder. But there is no way back for her now. She's the worst contestant - ever."
Biggins also said that he was not surprised his friend Nigel Havers lasted such a short time in the jungle.
He added: "I think poor Nigel believed he was going to spend the time having interesting conversation with a dozen intellectuals. It's not like that."
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