Australia has created the world's largest marine reserve, covering over 3 million sq km of ocean. It includes the entire Coral Sea and over a third of Australia's waters.
It will restrict fishing and mining and is a huge step in safeguarding the marine environment.
The announcement was made by Environment Minister Tony Burke. He said: "It's time for the world to turn a corner on protection of our oceans. And Australia today is leading that next step.
"This new network of marine reserves will help ensure that Australia's diverse marine environment, and the life it supports, remain healthy, productive and resilient for future generations."
The protection of the Coral Sea area which surrounds the Great Barrier Reef in the northeast is the "jewel in the crown" in the new scheme which will also see the number of marine reserves off the Australian coast increased from 27 to 60.
"The Coral Sea marine national park...combined with the Great Barrier Reef area, becomes the largest marine protected area in the world," Burke said.
"What we've done is effectively create a national parks estate in the ocean."
Australian Conservation Foundation chief executive Don Henry said the reserves would cover the breeding grounds of 45 of the world's 78 whale and dolphin species, six of the seven known species of marine turtle, and 4000 fish species.
However, the plan has drawn fire from the fishing industry which says it goes too far and will directly impact some of its most significant fisheries, while Australia's Greens Party says it doesn't go far enough, as the plan excludes large coastal areas off Western Australia which it says amount to a "surrender" to the oil and gas industry.
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