World powers have agreed to create the world's largest marine park off the coast of Antarctica. The landmark international agreement was brokered on Friday (28 October) in Australia by 24 countries and the European Union after years of negotiations.

The deal is now set to protect the pristine waters covering a massive 1.55 million sq km (600,000 sq miles) in the Southern Ocean. Of this, an area of around 1.1 million sq km — roughly the size of France and Spain — will be marked as a "no-take" general protection zone where commercial fishing and mineral extraction will not be permitted for 35 years.

However, some areas are believed to be designated as research zones where fishing for krill, a staple food for species including whales, seals and sawfish will be allowed.

The breakthrough in talks came after two weeks of discussions at the annual meeting of the Commission for the Conservation of Antarctic Marine Living Resources in Hobart, Australia. The delegates backed a proposal by New Zealand and the US, which had called to establish a marine protection area in the Ross Sea, one of the world's most ecologically significant oceans.

It is reported that scientists describe the Ross Sea as the "last ocean" as they claim it to be the most pristine water left on earth.

The sea comprises only 2% of the Southern Ocean but is thought to be home to more than 10,000 species including seabirds, colossal squid, 38% of the world's Adelie penguins, 30% of the world's Antarctic petrels and about 6% of the world's population of Antarctic minke whales, the BBC reported.

The deal is said to be a compromise as the US and New Zealand had originally proposed to protect the area for 50 years. However, Russia reportedly blocked similar proposals on five previous occasions, allegedly due to concerns over fishing rights.

Friction between Russia and the West has been reported to have caused the delay in the deal. However, on Friday (28 October), Russia and other parties ultimately agreed to the deal, which is said to likely set a precedent for creating other marine protection areas, experts believe.

Evan Bloom from the US State Department, who headed the US delegation to the meeting, told the Guardian: "I think it's a really significant moment. We've been working towards this for many years. It's taken time to get consensus but now we have established the world's largest marine protected area."

"The Ross Sea Region MPA [marine park authority] will safeguard one of the last unspoiled ocean wilderness areas on the planet — home to unparalleled marine biodiversity and thriving communities of penguins, seals, whales, seabirds, and fish," Reuters cited US Secretary of State John Kerry as saying.

Environmental activists and scientists have called the deal, which is expected to come into force on 1 December 2017, a historic milestone in efforts to protect global marine diversity.

"I'm absolutely overjoyed," BBC quoted Lewis Pugh, the UN Patron for the Oceans as saying. He has campaigned for years in support of the new marine park.

"This is the biggest protected area on the land or the sea, this is the first large scale MPA on the high seas, they are largely unprotected."

Phillipa Ross, great-great-great granddaughter of Sir James Clark Ross, after whom the Ross Sea is named, said: "The Ross family are euphoric that our family legacy has been honoured in the 175th anniversary year since James first discovered the Ross Sea."