Documents released by US whistle blower Edward Snowden allegedly show New Zealand links to mass surveillance from overseas spy agencies, a new book on his revelations show.

The documents were published in journalist Glenn Greenwalds book, No Place to Hide, which tells the story of Snowdens disclosures.

Links between NZ and NSA have been revealed before, when Snowden said last year that NZ was involved in mass spying. The New Zealand Government

One NSA document told New Zealands security services and those of other Five Eyes nations to "sniff it all, know it all, collect it all, process it all and exploit it all".

The Five Eyes is a spying alliance between New Zealand, Britain, Canada, Australia and the United States.

A slideshow showed Government Communications Security Bureau spies how to operate a system that trawled through massive amounts of phone numbers, email addresses and online chat.

Other files state New Zealand was forwarded intercepted phone calls, texts and emails between the Brazilian president and her staff.

GCSB was also briefed on NSAs efforts to put back doors into private companies computer networks, and given access to a program called Homing Pigeon which allowed in-air passenger jet conversations to be monitored, according to the book.

Spy boss Ian Fletcher last week refused to confirm if Snowden had files relating to New Zealand and if so, what they contained.

Prime Minister John Key has earlier said he had no concerns about Snowden's revelations, and that they would not challeged the integrity of GCSB.

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NSA tells NZ spies: 'Sniff it all'