Domestic security threats will be more closely examined by a reformed government intelligence bureau.

The External Assessments Bureau announced on its website that it has been renamed the National Assessments Bureau. The Green Party says this is a "huge change", creating a "domestic spy agency" that should have been subject to Parliament's scrutiny.

The name change marks a change of emphasis for the bureau, with more work being done on intelligence within New Zealand. The staff and budget have not increased from the existing 30 people and $3.5 million.

The change follows a review of the Government's three security services by former foreign affairs secretary Simon Murdoch. Besides the new bureau, the Government also relies on the Security Intelligence Service (SIS) and the Government Communications Security Bureau for intelligence.

The National Assessments Bureau is a unit of the Department of the Prime Minister and Cabinet, and will now provide more advice on threats from within as well as from overseas.

Prime Minister John Key said the change reflected the need for intelligence agencies to make sure people were safe ahead of the Rugby World Cup next year.

"So, in that regard, it is a National Assessments Bureau as opposed to [being] purely external."

Green Party foreign affairs spokesman Keith Locke said a lack of consultation over the change treated Parliament and the public with contempt. "It is a bit sad where the only growth area in the public service is in the spy agencies, who are quite unaccountable to the general public."

A beefed-up domestic security effort by the new bureau could create confusion and crossover with the work being done by police and the SIS, he said.