"We must finalise and adopt a federal law on the southern border of Russia's Arctic zone," Mr Medvedev told a meeting of the Security Council, in remarks carried by Interfax news agency.
"This is our responsibility, and simply our direct duty, to our descendents," he said. "We must surely, and for the long-term future, secure Russia's interests in the Arctic."
Global warming has stepped up the fight for the disputed Arctic, believed to be laden with vast reserves of oil and gas. Russia has pitted itself against Canada, Denmark, Norway and the United States to fight for a greater part of the region, arguing that most of it is Russian territory since an underwater ridge links Siberia to the North Pole's seabed.
Last August, a Russian mini-submarine carrying politicians and scientists plunged to the depths of the Arctic and claimed to plant a Russian flag to mark Moscow's stake in the territory.
Footage of the alleged planting was widely broadcast on Russian television – but later turned out to be images taken from the Hollywood blockbuster Titanic.
Canada has been preparing to contest the north by force if necessary, as I noted a year ago:
Ottawa said last month it would spend C$3.1 billion to buy at least six new patrol ships for the area.
The government said on Friday it will also spend C$4 million refurbishing a facility in Resolute Bay that will allow year-round training of military forces in the Arctic.
Rest assured that the Canadians aren't relying on special effects to defend their interests.
Canada could become NATO's front line if the Russians persist in looking for trouble wherever they can find it.