The expedition to explore the bottom of the Arctic Ocean and stake Moscow's claim to oil and natural gas riches under the sea bed ground to a sudden halt Wednesday when the Akademik Fyodorov research ship broke down in the Barents Sea.
The ship, which set sail Tuesday from the northern port of Murmansk, resumed its voyage Thursday, the Rossiya television correspondent said. The expedition was being led by the Rossiya nuclear-powered icebreaker, which turned back and was now accompanying the research ship.
The mission is aimed at finding evidence that the North Pole sea bed is geographically linked to Russia and thus part of its territory. Two mini-submarines are to be launched from Akademik Fyodorov to confirm the work of an earlier Russian expedition, which said it found the link between the Eurasian continent and the underwater Lomonosov Ridge that runs across the North Pole.
Russian scientists have long maintained that Moscow has a right to the mineral riches beneath a chunk of the Arctic sea bed the size of Germany, France and Italy combined. The region is estimated to contain up to 10 billion cubic meters of hydrocarbons, along with diamonds and metal ores.
Under international law, the five Arctic countries - Russia, the United States, Canada, Norway and Denmark (through Greenland) - control an economic zone within 200 miles (320 kilometers) of their continental shelf. But the definition of the limits of that shelf are in dispute.
Russia first laid claim to wide swathes of undersea Arctic territory in the United Nations in 2001. But the four other polar countries have objected to this bid. Danish scientists maintain the Lomonosov Ridge is an extension of Greenland, making Denmark another claimant to the North Pole and its environs.