The mission is part of a race to assert rights over the Arctic, an icy wasteland that is rich in energy reserves and, as climate change melts the ice, could open up to form a lucrative shortcut for ships sailing between Asia and North America.

"The Arctic is Russian," expedition leader and parliamentary deputy Artur Chilingarov told Russian TV. "We are going to be the first to put a flag there, a Russian flag, at the bottom of the Arctic Ocean, at the very point of the North Pole."

One of their biggest worries is resurfacing at the same hole in the ice they dived into -- missing it could mean becoming trapped as the mini-submarine is not powerful enough to break through the ice.

International law states the five countries with territory inside the Arctic Circle -- Canada, Russia, the United States, Norway and Denmark, via its control of Greenland -- are limited to a 320-kilometre economic zone around their coastline. Source...