A New Zealand journalist, Nicky Hager, says New Zealand's spying on small Pacific Island countries creates a gross disadvantage for small countries when it comes to regional negotiations.
Nicky Hager has analysed documents released by the American whistleblower Edward Snowden.
He says the wholesale collection of electronic communication is done on behalf of the United States.
Mr Hager says the information can be retrieved and filtered when it comes to trade agreement negotiations, tuna fisheries negotiations or even bilateral aid talks.
"There is not an equal battle between the little countries and the big countries because the big countries know what the little countries are saying. They know what their public servants are talking about they know what their advisers are saying they know what the Prime Minister says on the phone if they want to know it. And so it's meaning that the inequalities between countries is made even greater."
Nicky Hager says more detailed reports about New Zealand's surveillance of its neighbours will be released in the coming days.