Russia triggered a fresh scramble for the oil wealth of the Arctic yesterday when President Medvedev called on his security chiefs to establish a formal border in the region.

Mr Medvedev laid claim to a vast tranche of the Arctic, telling his National Security Council that it had “strategic importance” for Russia. The US Geological Survey estimates that the region contains 90 billion barrels of oil, as well as gas reserves – all of it increasingly accessible as global warming shrinks the ice cap.

“We must wrap up all the formalities for drawing the external border in the continental shelf. This is our direct responsibility to future generations,” Mr Medvedev told the Kremlin meeting.

Nikolai Patrushev, the director of the council, said that Russia would defend its interests in the Arctic against rival claims from the United States, Canada, Norway and Denmark. “We must define the borders in the north of our country, where the Arctic lies. Our estimate is that it makes up 18 per cent of our territory. And we are saying that 20,000km of the state border runs in this region.”

The Federal Security Service under Mr Patrushev created a special Arctic Directorate in 2004 to further Russian interests in the region. He even flew to the North Pole to plant a Russian flag.

The order to assert the Kremlin’s rights came just over a year after a team of Russian explorers became the first to reach the Arctic seabed. They dived 4,261 metres (13,980ft) in two mini-submarines and planted a titanium flag on the ocean floor to stake Russia’s claim to an area of territory the size of Western Europe.

The expedition brought back soil samples as part of Russia’s campaign to demonstrate that the Lomonosov Ridge, an underwater shelf that runs through the Arctic, is an extension of its territory. Russia lodged a claim in 2001 to 463,000 square miles (1.2 million sq km) of the Arctic ocean with the UN Convention on the Law of the Sea. The UN asked for more scientific data and Russia is planning to submit a fresh application next year.

Canada, Norway, the US and Denmark – which has sovereignty over Greenland – all reject Russia’s arguments. Denmark and Canada claim that the Lomonosov Ridge is linked to their territories, while Norway is conducting a survey to strengthen its case. Under international law each country is entitled to control an economic zone within 200 miles of its continental shelf, but the limits of the shelf are disputed.

Canada’s then Foreign Minister, Peter MacKay, dismissed the Russian expedition as a throwback to 15th-century imperialism, saying: “You can’t go around the world and plant flags and say ‘We’re claiming this territory’.”

Russia’s descent to the seabed unnerved its rivals, however, by demonstrating its ability to enforce a physical presence in the hostile Arctic environment.

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