German energy company Wintershall said Wednesday it was claiming a leadership position in Norway with the start of operations in the North Sea.

Alongside the newly-formed Aker BP, the German company said it started production at the Ivar Aasen field in the Norwegian waters of the North Sea. With the start, Wintershall it was setting the groundwork to become one of the top producers in Norway.

"We are constantly gaining more and more experience in the development of projects on the Norwegian continental shelf," Bernd Schrimpf, a regional managing director, for the German company said in a statement. "Working closely with Aker BP has been very constructive and efficient."

Aker BP, a merger of Norwegian energy companies and a national subsidiary of BP, had a discovery confirmed last week near the Frigg field in the North Sea. Based on preliminary data, the Norwegian government put the estimated size of the discovery at between 25 million and 75 million barrels of recoverable oil equivalents.

Wintershall said the Ivar Aasen field has estimated reserves of 186 million barrels of oil equivalent and has a peak production capacity of 68,000 barrels of oil equivalent per day.

The German company said Ivar Aasen will be connected to infrastructure associated with the nearby Edvard Grieg field. Ivar Aasen is the third for Wintershall in Norwegian waters in the last two years.

Norway is among the leading oil and natural gas suppliers to the European economy apart from Russia. Preliminary data for November show an average production of 2.15 million barrels of oil, natural gas liquid and an ultra-light product called condensate, which is about 2 percent higher than figures from October.