A Norwegian subsidiary of British energy company Centrica said it unloaded some of its assets in Norwegian waters following a portfolio review.

Retroactive to Jan. 1, Centrica E&P Norway transferred its 30 percent working interest in three license areas over to regional counterpart Det norske.

"After a review of our portfolio we have decided to transfer our ownership in three licenses to Det norske," Dag Omre, a regional vice president for Centrica, said in a statement. "These licenses are no longer core to Centrica and we have other priorities we wish to focus on in Norway."

Combined, Centrica holds about 50 licenses offshore Norway, operates 13 of those and produces about 85,000 barrels of oil equivalent per day from the region.

Det norske in exchange covers the expenses to date for the three fields in the area. The deal for the Norwegian company, which says it's building one of the largest independent exploration and production companies in Europe, follows a string of acquisitions of offshore Norwegian assets, including the October grab of the entire regional subsidiary of British energy company Premier Oil.

According to data from the Norwegian government, there are roughly 18 billion barrels of oil equivalent yet to be discovered in Norwegian waters. Half of that is in the Barents Sea, with the rest distributed in the North and Norwegian seas.