A New Zealand-led proposal to create an enormous marine sanctuary off the Antarctic coast will be considered for a fifth consecutive year at international talks in Australia.
The New Zealand-US bid - along with another Australian-backed scheme - aimed at protecting marine life surrounding the frozen continent, will be discussed at the annual Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) meeting that begins in Hobart today.
Both bids were blocked by China and Russia last year.
New Zealand first proposed to designate a Ross Sea marine protected area (MPA) in 2011 but the bid has been met with significant opposition from the two heavyweights.
The plan for "The Last Ocean" has since been scaled back to 1.25 million square kilometres with 1.14 million square kilometres proposed as a "no take" zone.
Meanwhile, the Australian-backed East Antarctica scheme has also been watered down from a 1.9 million square kilometre MPA, to a 946,998 square kilometre zone with some fishing and research allowed provided conservation values are met.
Despite the compromises, environmental groups are doubtful of a solution.
"CCAMLR promised that this protection would come by 2012, yet the process has been stalled for the last four meetings," Antarctic and Southern Ocean Coalition executive director Mark Epstein said.
"Global leaders - many of whom are CCAMLR members - have a responsibility to take action now, ensuring these marine protected areas come into force at this meeting."
Both plans must win the support of all 25 members of CCAMLR to succeed.
Environmentalists say the Southern Ocean is the world's last untouched wilderness and home to more than 10,000 unique species, including penguins, whales and colossal squid, as well as being a region critical for scientific research.
CCAMLR is a treaty-based group tasked with overseeing conservation and sustainable exploitation of the Antarctic Ocean with talks to continue until October 30.