"Production has been reduced by 50 percent since Monday morning. If the weather permits, we will begin producing at full capacity next weekend," Statoil spokesman Harald Schjeldrup told AFP.

In normal circumstances, the ship operating in the field extracts about 100,000 barrels of oil equivalent (boe) per day.

A severe storm has been raging along the coast of Troendelage in western Norway, with winds of 67 knots (77 miles) an hour and waves in some places towering 18 metres (59 feet).

Norway, the world's largest oil exporter after Saudi Arabia and Russia, normally produces nearly three million boe per day.