A decision is expected on Friday on whether to protect a vast area of Antarctica's Ross Sea.
The headquarters of the CCAMLR. Photo: RNZ
New Zealand and American officials have until Friday night to convince 23 other countries that 1.3 million square kilometres of the ocean needs protecting.
If agreement is reached at a meeting of the Commission for the Conservation of Antarctic Marine Living Resources in Hobart, the world's largest protected marine area would be created.
Negotiations on Thursday went well into the night, particularly with the main fishing nations, who are concerned about losing access to the commercial fishery.
The New Zealand delegation said on Thursday it was optimistic about reaching a deal in time.
The delegates have until about 7pm on Friday to confirm whether the protected area will be established, or negotiations will have to resume at a future meeting.
