Royal Dutch Shell PLC says it has agreed to sell its stake in the Statfjord oil field in the Norwegian North Sea and several related assets to Centrica Resources AS for $225 million. Shell said Friday its share in the mature field, 9.4 percent, produced 13,300 barrels of oil a day last year. Other major owners include Statoil, ExxonMobil and ConocoPhilips. The Associated Press quoted Shell as saying that it was selling the asset as part of a plan to raise at least $7 billion by 2011 to reinvest in growth projects. Shell remains active in several other projects in Norway, including some that are still being built. Friday's deal must be approved by regulators.