Attempts to prevent Russia from extracting the Arctic's mineral resources are unacceptable, President Medvedev said at a Security Council meeting in Moscow.
Medvedev said climate change could increase rivalry over the Arctic deposits which could hold an estimated 25% of all global oil and gas reserves.
He says some countries are now trying to limit Russia's access.
In 2007, explorers planted a Russian flag on the Arctic seabed in a symbolic territorial claim that the so-called Lomonosov Ridge is an extension of Russia’s territory.
The move was denounced by Canada and Denmark, and the countries bordering the Arctic signed a treaty agreeing to abide by existing borders, which are regulated by the United Nations Convention on the Law of the Sea.