British Gas owner Centrica has said it is to double its interest in a North Sea oil and gas field.
Centrica says the deal will deliver additional gas to the UK
It has reached agreement with BP subsidiary Britoil to increase its stake in the Statfjord field, which will deliver more gas to the UK market.
Centrica will pay $266m (£151m) to buy BP's 4.84% holding in the field.
Centrica recently announced an 11% rise in operating profit to £1.5bn for 2005. And British Gas raised prices by 22% recently, blaming high wholesale costs.
Sir Roy Gardner, chief executive of Centrica, said: "We have delivered significant value from our current interest in Statfjord and now have the opportunity to increase our presence in one of the North Sea's largest fields which will deliver additional gas into the UK market.
"This is in keeping with our upstream strategy, to build our portfolio of high quality producing assets and medium term development opportunities to supply our British Gas customers."
Statfjord is an oil field that is on the border between the Norwegian and British sectors of the continental shelf in the North Sea, in around 145 metres of water.
The deal should add an additional 65 billion cubic feet (bcf) of gas and 14.5 million barrels of oil to Centrica's portfolio.
The company acquired its original 4.84% interest in Statfjord, one of the largest fields discovered in the North Sea, from Chevron Texaco two years ago.
Statfjord is currently an oil producing field with associated gas which will be re-engineered to focus on gas production.
Centrica's additional share of the associated capital expenditure for the project will be roughly £50m.
A new export pipeline from the Statfjord field to the Flags pipeline into St Fergus will also enable additional quantities of gas to be delivered to the UK market.
Statfjord is situated on the border of UK and Norwegian waters. Centrica intends to increase its participation in the Norwegian oil and gas sector, having pre-qualified as an operator in Norway in 2005.
In August, Centrica said it was to buy stakes in four North Sea oil and gas fields from Kerr McGee for £318.6m.