Russia pressed a claim at the United Nations Tuesday for an additional 1.2 million square kilometres (463,000 square miles) of Arctic shelf, stepping up a race for the region's hydrocarbon and mineral wealth.

In a submission to back a 2001 claim at the UN Commission on the Limits of the Continental Shelf, Russia said research showed it had rights over the swathe -- an area the size of South Africa.

This would include the North Pole and potentially give Russia access to an estimated 4.9 billion tonnes of hydrocarbons, according to government estimates.

The Arctic has become a theatre for rival claims over a sea floor believed to be rich in minerals, oil and gas.

Under international law, a country has exclusive economic rights over the continental shelf within a 200-nautical-mile (370-kilometre) radius from its coast.

However Arctic nations have been jostling to claim greater areas.

They have been spurred by the shrinkage of Arctic sea ice, which opens up the potential for new transport routes and mineral and energy exploitation.

Russia says extensive research spanning several years proves its continental shelf extends far beyond the 200-nautical-mile radius.

Its claim includes the Mendeleev Rise as well as the Lomonosov Ridge, which Denmark and Canada also say is theirs. Russia argues they, like the North Pole, are part of the Eurasian continent.

Russia previously submitted a claim to the UN commission in 2001 but was told it lacked supporting scientific data.

- 'Limit others' access' -

The commission returned the document -- which was mostly based on Soviet-era studies -- with over 160 recommendations, said Viktor Poselov, a deputy director of research at the VNII Okeangeologia Institute in Saint Petersburg, which worked on both the initial and updated claim.

Over the last decade, nine expeditions, each costing up to a billion rubles ($16 million, 14.6 million euros), ventured into the Arctic to collect seismic data and map the ocean floor over tens of thousands of kilometres, he said.

If the new proposal is accepted by the UN commission, Russia would not only gain the right to the mineral deposits but also have an argument in favour of expanding its frontiers, Poselov told AFP.

"We would set a border that would limit other states from accessing this area," he said.

As for contested areas like the North Pole, their status would have to be resolved diplomatically, he said.

"The question of the North Pole would have to be addressed, whether to leave it as the common property of the international community," he said.

Denmark also claimed the North Pole in a proposal submitted in 2014, although it could be years before the commission formally reviews the research.

Canada filed an Arctic seabed claim in 2013 but later withdrew the proposal and is drafting a new one.

- 'Very interesting deposits' -

Norway and Russia formally put an end to a longstanding Arctic dispute in 2010 by signing an agreement on delimitation in the Barents Sea.

Russia's foreign ministry said the country's submission had "priority" status, and Poselov said he expected it to be reviewed in February.

After that, it could take up to three years to ensure the scientific data in the 2,000-page document is legitimate, he said.

"There are definitely very interesting deposits there, but the question is how accessible they are," he said.

"The conditions are very difficult, it's an issue for the future."

Greenpeace said the claim endangered the area around the North Pole that is already vulnerable to climate change and called for nations not to treat it as "the next Saudi Arabia."

"Unless we act together, this region could be dotted with oil wells and fishing fleets within our lifetimes," Greenpeace Russia's Arctic campaigner, Vladimir Chuprov, said in a statement.

President Vladimir Putin has strengthened Russia's focus on the Arctic in recent years and the country boldly planted its flag on the sea bed under the North Pole in 2007.

The Russian government established a special commission for Arctic development this year to oversee economic projects and national security in the region.

Russia also held war games in the region, even sending paratroopers to an ice floe.

Last week, it announced that its revised navy doctrine would be heavily concentrated on the Arctic area.

ma/ri/ser

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