Kim Dotcom claims he has proof that Prime Minister John Key lied about not knowing who the Megaupload millionaire was until just before the raid on his Coatesville mansion.
But Dotcom says he will not reveal his evidence until he is in court.
Dotcom told TVNZ's Q+A programme this morning that Mr Key knew about the German-born millionaire living in New Zealand before the Prime Minister was briefed on January 19 about the next day's planned police raid on his mansion.
Mr Key today denied the allegation by Dotcom.
A spokesman for the Prime Minister said he "stands by his earlier statements" about when he first knew about the internet entrepreneur.