UK GAS-Prices decline on higher flows from Norway

May 31 (Reuters) - British wholesale gas prices declined on Wednesday morning, mainly due to higher flows from Norway through the Langeled pipeline. * British day-ahead gas price down 0.80 pence at 37.60 pence per therm at 0841 GMT. * Within-day contract down 0.85 pence at 37.55 p/therm. * Flows through the Langeled pipeline from Norway are 24 million cubic metres (mcm) higher than on Tuesday. * The system was oversupplied by almost 18 mcm, with demand forecast at 190 mcm and flows at 208 mcm/day, National Grid (LSE: NG.L - news) data showed. * June gas contract was down 0.40 pence at 36.90 p/therm. * Day-ahead gas price at the Dutch TTF hub 0.10 euro lower at 15.48 euros per megawatt hour. * Benchmark Dec-17 EU carbon contract was down 0.06 euro at 5.08 euros per tonne. * Thomson Reuters (Dusseldorf: TOC.DU - news) analyst view: http://emea1.apps.cp.extranet.thomsonreuters.biz/cms/?pageid=united-kingdom-gas (Reporting by Nina Chestney)