"These areas are very vulnerable and important for seabirds and sea mammals like polar bears and walruses," Environment Minister Boerge Brende said of the new conservation area for the Svalbard islands, 1,000 miles (1,600 km) from the North Pole.

The government said it was extending the marine protection zone around Svalbard to 12 nautical miles from four, adding an area of 41,000 square km (15,830 sq mile) - the size of the Netherlands or Switzerland.

On Monday, the government decided to lift a two-year ban on oil and gas drilling in the Arctic Barents Sea but shielded the scenic Lofoten islands south of Svalbard after pressure from environmentalists and the fishing industry.

"This is a double Christmas present for everyone who cares about the environment," said conservation organisation WWF's Arctic Programme head Samantha Smith of the Svalbard and Lofoten decisions.

"We hope this is a precedent for other areas in the Barents Sea under threat from oil and gas development," she said.

Norway is the world's third biggest oil exporter behind Saudi Arabia and Russia, pumping about three million barrels per day. But finds in the North Sea are drying up, pushing oil companies to seek new Arctic areas.

Svalbard is a coal mining centre and some oil companies reckon it could offer interesting prospects. In September, the government set aside about 4,500 sq kms of the land on Svalbard as a conservation park.