An expedition aimed at boosting Russian claims to much of the Arctic Ocean has reached the North Pole. Two Mir Submarines have dived 4,200 metres to the Ocean floor to carry out experiments and plant a capsule containing the Russian flag. The Rossiya nuclear icebreaker ploughed a path through the ice clearing the way for the research vessel the Akademic Fedorov. Under international law, the five states with territory inside the Arctic Circle-Canada, Norway, Russia the United States and Denmark have a 320 kilometre economic zone around the north of their coastlines. But Russia is claiming a larger slice extending as far as the North Pole because the Russians believe the Arctic seabed is linked to Siberia.