Russia makes renewed bid for contentious Arctic regions
Russia has renewed its efforts to get the United Nations to recognise 1.2 million sq km (463,000 sq miles) of the Arctic shelf that it lays claim to.
It made a similar move for the resource-rich territory in 2001, but that was rejected by a UN commission because of insufficient evidence.
Russia's foreign ministry said the fresh bid is backed by scientific data.
But all other countries bordering the Arctic - Norway, Denmark, Canada and the US - reject Moscow's claim.
All five nations have been trying to assert jurisdiction over parts of the Arctic, which is believed to hold up to a quarter of the world's undiscovered oil and gas.
The competition for Arctic resources has intensified in recent years as the shrinking polar ice opens new opportunities for exploration.
Russia said its new submission to the UN Commission on the Limits of the Continental Shelf contained new arguments.
"Ample scientific data collected in years of Arctic research are used to back the Russian claim," Russia foreign ministry said in a statement.
Russia previously staked a claim to the Arctic seabed in 2007 by dropping a canister containing the Russian flag on to the ocean floor from a submarine at the North Pole.
The new move comes a week after the Kremlin said it was strengthening its naval forces in the Arctic as part of a new military doctrine.
Russian Deputy Prime Minister Dmitry Rogozin said the plans included a new fleet of icebreakers.
Earlier this year, Russia's military conducted exercises in the Arctic that involved 38,000 servicemen, more than 50 surface ships and submarines and 110 aircraft.