The acquisition raises Centrica’s overall interest in the Statfjord field to 19.13% and also provides the company a 6.07% interest in the Sygna field, 5.52% in the Statfjord East field and an 11.04% interest in the Statfjord Nord field.

The gas produced from these fields is uncontracted and is directly linked to the UK market.

This acquisition will provide Centrica with an additional 172 billion cubic feet equivalent of gas and oil reserves, and an incremental 70 million cubic feet per day of natural gas and oil production in 2010.

Centrica Energy managing director Mark Hanafin said that this represents a further step in Centrica’s strategy to grow and deliver value from its upstream business.

"It also increases our level of gas reserves to supply British Gas customers and underlines our continued commitment to invest in North Sea production," Hanafin said.

Exxon Mobil, ConocoPhilips and Statoil also own stakes in the Statfjord field, which is operated by Statoil.