Prime Minister John Key yesterday sought another assurance from GCSB director Ian Fletcher that the spy agency had not been involved in wholesale collection of metadata on New Zealanders - and was given it.
But Mr Key was unable to tell reporters later whether the United States National Security Agency collected wholesale information on New Zealanders for its purposes.
"I don't know," he said.
Mr Key sought the assurance from the GCSB after a leaked intelligence memo yesterday passed from ex-NSA contractor Edward Snowden to the Guardian newspaper.
The memo leaked to the Guardian shows that the GCSB's Australian equivalent in 2008, DSD, offered to supply wholesale metadata on Australian citizens to its Five Eyes intelligence partners, the US, Britain, Canada and New Zealand.
The memo suggests that the Australian spy agency intended to get around its own laws of not targeting Australian nationals by bulk collection of raw metadata and not targeting anyone in particular. "Unintentional collection is not viewed as a significant issue," the memo said.
It is not clear whether the intended sharing of bulk data went ahead.
Mr Key said yesterday: "I rang the head of the agency and said, 'Can you confirm for me that New Zealand didn't collect wholesale metadata about ordinary New Zealanders?' and the answer was, 'We didn't, and because we didn't, we couldn't have shared it'.
"We share information in isolated cases about New Zealanders with our partners, and we do that when there's a really good reason to do that."
Mr Key also said the GCSB did not get other countries to collect information on New Zealanders to circumvent New Zealand law.
Asked whether the NSA collected wholesale information on New Zealanders for their own purposes, he said: "I don't have the answer to that - I don't know."
Talking to 3News this morning Prime Minister John Key denied the revelations that Australia's spy agency offered to supply wholesale metadata to its Five Eyes partners would shake New Zealanders confidence in the GCSB, saying: "No, I don't think so."
While he said it was "highly likely" that whistleblower Edward Snowden would have information about New Zealand among the data he is releasing from the US National Security Agency, he said he was not worried by what may be exposed.
"I'll be amazed if people are that surprised by the things that they hear, it'll be pretty selective.
"The reality is, these are intelligence agencies, where appropriate for national security and the national interest, they collect intelligence - that's what they're there to do, and they are there to keep New Zealanders safe."
Is Edward Snowden a Russian spy?
Former intelligence and defence policy analyst Dr Paul Buchanan says it is possible.
In a column in today's Herald, Dr Buchanan said the leaks so far raised questions over why Snowden had not released information about Chinese and Russian spying activity. He said the NSA had a lot of information about its opponent nations and none of it had been part of the series of leaks which had damaged the US.
- Additional reporting by APNZ