A tiny Pacific Ocean island nation that exerts control over a huge area of ocean waters says it will create a vast marine park the size of the state of California in which all commercial fishing will be banned.

The country of Kiribati, an island chain halfway between Fiji and Hawaii, will end all commercial fishing in its Phoenix Island Protected Area at the start of 2015, Kiribati President Anote Tong announced at the Our Ocean conference in Washington, D.C., hosted by the U.S. State Department.

"We will also close the area around the southern Line Islands to commercial fishing to allow the area to recover," said Tong.

The southern Line Islands along with the Phoenix Islands host what are considered among the most unspoiled coral reef ecosystems in the Pacific Ocean. Kiribati is about 1,250 miles from Hawaii and 5,000 miles from Australia.

The Kiribati announcement comes as U.S. President Obama made one of his own, that he intends to form the world's biggest ocean preserve inside of which fishing, drilling and other commercial activities will be banned.

His proposal, which would constitute the world's biggest marine sanctuary, would double the amount of the world's oceans put under full protection.

Obama's proposal, which doesn't require Congressional action, would expand the existing Pacific Remote Islands Marine National Monument, originally created by President George W. Bush.

The waters within are all designated U.S. territory since they surround a U.S.-controlled array of far-flung and mostly uninhabited islands between American Samoa and Hawaii.

Such protections are necessary to halt the damage to marine ecosystems and marine life caused by ocean acidification, pollution and overfishing, the president said in a recorded video message presented at the ocean conference.

"If we ignore these problems, if we drain our oceans of their resources, we won't just be squandering one of humanity's greatest treasures," he said. "We'll be cutting off one of the world's major sources of food and economic growth, including for the United States. We cannot afford to let that happen."

The ultimate boundaries of the preserve have not yet been decided, with the president asking for input from scientists, conservationists, fishermen and politicians, the White House said.

Maritime law gives countries economic control in waters within 200 nautical miles of their coastlines.

Taking into account all U.S. possessions located in the Pacific region, the president's proposal would create a preserve of more than 780,000 square miles, a geographic analysis by the Pew Charitable Trust found.

While there is currently little fishing and no drilling under way in those waters the president's proposal would add to the protected area, conservationists applauded Obama's proactive step.

"Anywhere there are fish to be extracted or minerals or resources, these locations are under threat from commercial extraction," said Matt Rand, the head of Pew's global ocean legacy project.