Opposition parties say fresh disclosures about the illegal spying operation against Kim Dotcom make an independent inquiry inevitable.
An audit of the Government Communications Security Bureau's files has revealed a presentation was given to Prime Minister John Key in February this year which made a brief mention of the GCSB's Dotcom operation.
That is contrary to repeated statements by Mr Key that he was first made aware of the case on 17 September. He said on Wednesday he does not remember it being raised, but accepts that it happened.
Three out of the bureau's 58 operations also need further work to determine whether they were lawful.
Opposition parties say this all gives impetus to their call for an independent inquiry, but Mr Key says enough is already being done.
United Future Future leader Peter Dunne says there is no need for an independent inquiry and doubts one would yield much useful information due to the confidential nature of the GCSB.
Mr Dunne told Radio New Zealand's Morning Report programme on Thursday that Mr Key has done all he can to ensure the spy agency acts lawfully.
Kim Dotcom's lawyer, Ira Rothken, told Morning Report there also needs to be an independent investigation of possible police misconduct in the operation and his client's case should be dismissed in the interests of justice.
Labour Party leader David Shearer says the Prime Minister has no excuse for not remembering a briefing on the Kim Dotcom saga that he received long before the matter became public.