The Soviet Union maintains that its territorial waters, including those in the Arctic, extend 12 n mi from its coastline. It has also declared a "sector claim" asserting Soviet sovereignty over all lands and islands in the triangular Arctic Basin sector bounded by lines that extend due north from its Arctic coasts to the North Pole. Subsequently, Soviet jurists have unofficially interpreted the sector principle to mean that the USSR also claims the airspace above the sector as well as the ice islands, the ice pack, and the waters between the islands and between the islands and the mainland. The Soviet government has not officially repudiated these interpretations, though present Soviet policy does seem to recognize the "high seas" status of the Arctic Ocean and its airspace. These claims may become troublesome with the advent of surface-effect vehicles and submarine transports that will permit regular Arctic navigation.