A furious row between the two men campaigning to be leader of the Liberal Democrats as Chris Huhne's team circulate a document entitled "Calamity Clegg".
But Chris Huhne has denied authorising such a briefing paper.
Mr Huhne, the party's environment spokesman, told Jon Sopel he had no knowledge of the document.
But, in heated exchanges, he went on to accuse home affairs spokesman, Nick Clegg, of "flip-flopping" over his policies.
Mr Clegg said Mr Huhne was trying to create "synthetic differences" which "our opponents will use against us".
A spokeswoman for Mr Huhne said the title of the leaked document, "Calamity Clegg", had been thought up by an "over-zealous researcher".
She added that Mr Huhne stood by the contents of the document - a list of quotations which she said showed Mr Clegg's policy "flip-flops".
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