The Green Party is worried a proposal for a marine protected area in Antarctica's Ross Sea could allow for commercial fishing under the guise of science.
The deal between New Zealand and the United States was signed on Monday. It is understood to involve just over 2.2 million square kilometres of the Ross Sea becoming a protected area and the establishment of a research zone where fishing can occur.
Twenty-three other countries at the Commission for the Conservation of Antarctic Marine Living Resources are being asked to support it at a meeting in Hobart, Australia, before a vote on Thursday.
The Green Party's ocean spokesperson says 600,000 square kilometres of the Ross Sea is expected to be part of the lightly fished research zone.
Gareth Hughes believes it could simply be a back door to commercial fishing, similiar to Japan's scientific whaling.
The Ross Sea is of tremendous ecological, conservation and scientific importance to current and future generations, he says.