Kim Dotcom says he has proof that Prime Minister John Key has lied about not knowing who the Megaupload millionaire was until just before the raid on his mansion.
But Dotcom says he will not reveal his evidence until he is in court.
Dotcom told TV3's Q+A programme this morning that Mr Key knew about the German-born millionaire living in New Zealand before he was briefed on January 19 about the next day's planned police raid on his mansion.
Mr Key has continually denied such claims, repeatedly saying it was the first time he became aware of the Megaupload founder.
"He is running around naked and telling everybody he has clothes on,'' Dotcom told Q+A.
"Everyone can see he's naked. It doesn't make any sense.
"I know for a fact that John Key knew before January 19.
"It's going to be a topic in our court hearing so I don't want to reveal too much.''
Dotcom is fighting extradition to the US where authorities allege copyright, money laundering and fraud charges in relation to his file-sharing website.
The Megaupload founder said there was "only one reason'' why Mr Key would "not be upfront and honest''.
Dotcom claimed it showed there was political interference in the investigation and proving that could "stop the whole extradition procedure''.
"If we can show that the government here has had an active role in the magnitude of this whole case and had a proactive role _ rather than a reactive role _ to impress the United States government... it's a monster issue,'' Dotcom said.
Meanwhile, Dotcom said he was "hurt'' by ACT leader John Banks when the politician declined to help get him a thicker mattress for his prison cell after being arrested in January.
Dotcom said he considered Mr Banks "a friend'' and explained to Q+A that he had been asked by the ACT leader to make his infamous $50,000 donation in two cheques so that it would stay anonymous.
Mr Banks said he could not help get a thicker mattress for Mr Dotcom, who suffered "major back pain'' due to his "weight and health problems''.
"If I call myself a friend of someone and that person gets into trouble, I'd try to help.
"I would say [I was] hurt.''
