Talks to create the world's two largest marine reserves in the Antarctic have broken down, with conservationists branding Russia a "repeat offender" for blocking an international agreement.

Delegates from 24 nations and the European Union have been locked in talks in Hobart for the past 10 days at the annual meeting of the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR). But the negotiations have ended in frustration for the nations, including Australia and the US, that proposed vast protected zones around Antarctica, with Russia, Ukraine and China refusing to back the plans. The US and New Zealand had proposed a 1.3m square kilometre protected area in the Ross Sea. A separate plan put forward by Australia, France and the EU would have kept 1.6m square kilometres of East Antarctica off-limits to fishing. Consensus among the nations was required to ratify the plans. The failure of the talks is the third time in the past year that the proposals for protected zones have failed to find agreement among the commission's nations. Previously, Russia and Ukraine questioned the legal status of the protected areas. Andrea Kavanagh, the director of The Pew Charitable Trusts' Southern Ocean sanctuaries project, told Guardian Australia that the failure of the talks was "incredibly disappointing". "It's a bad day, not just for Antarctica but for the world's oceans, because so many fisheries are over-exploited and this was the one place we could create a reserve," she said. "The fact it can be blocked by a few nations with interests in fishing is very hard to take. "Russia and Ukraine filibustered until the end. They wanted to open up more areas for fishing and set a time limit of 10 years. Given that it has taken that amount of time to draw up the protected zones, we would've spent more time planning this than protecting it, which is ridiculous. "I think conservation-minded countries need to take a stand and tell Russia this is unacceptable. There's no reason why fishing nations such as Australia can put up protected zones only for other fishing nations to block them." The Antarctic waters are home to more than 10,000 unique species, including most of the world's penguins and the rare toothfish. The region is considered by scientists as vital to the health of the world's marine life. It is estimated that three-quarters of all aquatic life is sustained by the nutrient-rich waters of the Southern Ocean, which are transported by an enormous current into the northern hemisphere. The commission will reconvene in Hobart again in October 2014, although conservationists aren't hopeful of a better result. "What we have witnessed over the past few years is the steady erosion of the spirit and mandate of CCAMLR to conserve the last intact ocean ecosystem remaining on earth," said Farah Obaidullah, Greenpeace International oceans campaigner. "This year's failure denigrates the reputation of CCAMLR and is symptomatic of a dangerous global trend where corporate and political interests override any genuine efforts to protect the oceans for the sake of future generations."

Australia's environment minister, Greg Hunt, was more upbeat. "I think we have made enormous progress this week on marine protected areas for the Antarctic. We've laid the foundation for the future, great progress. The next time I think we can achieve something that has eluded everybody for decades."