The Prime Minister says he can assure New Zealanders that any information-sharing activity carried out by intelligence agencies is done within the law, Radio New Zealand reports.
John Key has confirmed information gathered by the Government Communications Security Bureau could have been used in identifying targets for American attacks using unmanned aircraft.
However, he said the GCSB did not supply information leading to the death of New Zealander Daryl Jones in a drone strike in Yemen last year.
The Green Party says it is not just a matter of whether agencies are acting within the law.
Co-leader Russel Norman said there are serious ethical questions about New Zealand's supplying information that may lead to extra-judicial killings.
Defence analyst Terence O'Brien said New Zealand's membership of the Five Eyes intelligence network needs to be more widely debated.
O'Brien, a senior fellow at Victoria University's Centre for Strategic Studies, said Five Eyes is being used to help the pursuit of the war on terror.