Prime Minister John Key has once again given his assurance there is no mass electronic surveillance of New Zealanders.
The American journalist Glenn Greenwald - to whom the fugitive security analyst Edward Snowden leaked documents last year - told TV3's The Nation this morning the New Zealand Government had engaged in extraordinary amounts of metadata analysis, both internationally and within New Zealand.
On Monday, Mr Greenwald and Kim Dotcom will hold a public meeting in Auckland.
Mr Key has repeatedly said there is no mass surveillance of New Zealanders or collection of their metadata by the Government Communications Security Bureau (GCSB).
This afternoon, Mr Key would not speculate about what Mr Greenwald would say at Monday's meeting, but was adamant the Pulitzer Prize-winning journalist would be proved wrong.
"When you hack into people's information and you steal it, sometimes you get part of the information but not all of the information.
"Now, in the fullness of time we'll respond to Dotcom's little henchman, but mark my words, he's wrong. There never has been mass surveillance and there is no mass surveillance."
Labour leader David Cunliffe said it was up to Mr Key to answer whatever was revealed in the coming days.
"I think we need to see the evidence. It looks like the Prime Minister may not have been entirely frank with New Zealanders about, for example, the use of metadata, and I think New Zealanders will want to see the evidence."
He said the new allegations about New Zealand's spying activity, if true, were very serious and could be enough to swing the election Labour's way.
"I think the credibility and truthfulness of the Prime Minister of the day is always important and it is always fundamental to the trust of New Zealanders. If the Prime Minster of the country has lied to New Zealand, I expect New Zealanders will react in the ballot box."
He said it raised serious questions about whether the Government had been truthful.
"This is a very sensitive area where the Prime Minister's word must be able to be relied upon."
Mr Cunliffe said it would have been preferable if this information had been revealed much earlier.