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