The countries which regulate fishing in the Antarctic have been unable to agree on creating a giant marine sanctuary in the region.
The US and New Zealand had submitted a joint proposal to protect the Ross Sea, considered one of the most pristine oceans in the world.
Some nations remain concerned, however, that it would have too much impact on their catches of toothfish, which are marketed as Chilean sea bass.
The 24 nations and the European Union finished two weeks of meetings in Australia without coming to any agreement on the sanctuary proposal.
The countries will meet again next July to further consider the idea.
Earlier this week, New Zealand and the US finally resolved two years of negotiations over sanctuary boundaries and rules.
Scientists say an Alaska-sized sanctuary would make an ideal place to monitor climate change away from the influence of man while conservationists say the thriving colonies of seals and penguins should be left alone.
Fishing captains say their catch is relatively small and sustainable, and they want to keep the status quo. The joint proposal would have banned fishing altogether in some areas and allowed modest fishing in others, reflecting an uneasy compromise between the groups.
But at the meeting some nations, including Russia, Ukraine and China, balked at the proposal. They feared it would have too much impact on their annual haul of toothfish.
"It's disappointing but not entirely surprising," said Murray McCully, New Zealand's minister of foreign affairs. He said he plans to discuss the outcome soon with US secretary of state Hillary Clinton, who has taken a close personal interest in the issue. Mr McCully said that after the US elections he plans to devise a lobbying strategy with senior US officials to try and get the proposal passed at the meeting next July.