Vladimir Putin has long considered the Arctic a Russian "sphere of special interest," and on Tuesday, Russia formally petitioned the UN for a large chunk of Arctic territory. Russia is hoping to use a little-known international treaty — The UN Convention on the Law of the Sea — to claim a 460,000 square mile section of the frozen landmass that's thought to contain nearly 5 billion tons of oil.

The move is the latest in an international scramble for the oil-rich and strategically significant Arctic. In addition to Russia, the United States, Canada, Denmark, and Norway are all jockeying to claim chunks of the region, which some experts predict could hold a quarter of the world's untapped oil reserves and natural gas deposits.

"To justify Russia's rights in this area, a vast array of scientific data collected during many years of Arctic research has been used," the Russian Foreign Ministry said in a statement.

To bolster its claim, Russia is relying on the United Nations Convention on the Law of the Sea, which allows signatories to claim an exclusive economic zone up to 200 miles from their coastline or, crucially, as far as their territory "naturally extends" from shore beneath the sea. Russia is arguing at the UN that two of its underwater features — the Lomonosov Ridge and the Mendeleev Ridge — are natural geological extensions of the Russian continental shelf. Russia submitted a similar petition in 2002, but was rebuffed for lack of evidence.

In 2007, a defiant Russia dropped its flag on to the floor of the Arctic sea using a submarine. Moscow hopes that Tuesday's petition will formalize its claim on the Arctic soon.

"We expect the commission to start working on Russia's application as early as in the autumn of 2015," the Russian foreign ministry said.

But Russia is not the only country using the UN Convention on the Law of the Sea to exert control over the Arctic. Denmark made a similar claim in 2014, arguing that its Lomonosov Ridge — a 1,240-mile mass that cuts through the center of the Arctic Ocean — is actually part of Greenland. Norway and Canada are also expected to make similar arguments about the contested territory.

Still, Russia has not let international law stand in the way of its Arctic ambitions.

Over the past year, Russia has started to construct military bases and rebuild abandoned installation in the Arctic. It has also embarked on an ambitious construction blitz along its own coastline to project its influence into the contested territory, and has reportedly built 10 search-and-rescue stations, 16 deep-water ports, 13 airfields, and 10 air-defense radar stations along its Arctic coastline over the past several years.

In December, Russia announced the creation of the Joint Strategic Command North (JSCN) to oversee its permanent military presence in the Arctic. And In March, it conducted a massive five-day Arctic military exercise, involving some 80,000 troops, 220 aircraft, 41 ships, and 15 submarines. A few months later, reconnaissance and surveillance drones began flying over the disputed territory.

Since the 1980s, temperatures in the Arctic have increased twice as fast as the rest of the world, according to the UN Intergovernmental Panel on Climate Change, and energy exploration in the region is becoming increasingly attractive to nearby oil-producing states. Over the past year, Canada has been performing seismic test and testing the viability of oil exploration in the region. Meanwhile, Shell is ramping up its oil exploration on the Alaskan coastline, and in February, Russia's energy minister Alexander Novak announced that the Russian energy company Rosneft would spend $500 billion to explore the Arctic in the next 20-25 years.

But many environmentalists worry about the scramble for the Arctic. An oil spill in the remote region could be an environmental disaster, and even without such an event, the greenhouse gases unleashed by tapping into oil reserves could acerbate climate warming.

"The problem is that if they go up and spill, it's a disaster locally. If they go up and don't spill, and succeed, then it's a disaster globally," Greenpeace's Travis Nichols told VICE News in May.