UK GAS-Prices firm on reduced Norwegian, LNG supply

LONDON, Aug 18 (Reuters) - British prompt gas prices rose on Friday as falling imports from Norway and low send-out from liquefied natural gas (LNG) terminals created an undersupplied market. * British within-day gas price up by 0.75 pence to 43.55 pence/therm at 1052 GMT. * Day-ahead gas price up 1.10 pence at 43.85 p/therm. * Britain's gas system was seven million cubic metres (mcm/day) undersupplied with demand estimated at 174 mcm/day and supplies at 167.8 mcm/day, National Grid (LSE: NG.L - news) data shows. * Flows from Norway through the Langeled pipeline drop to 35 mcm/day from 42 mcm/day on Thursday. * Send-out from LNG import terminals remains low but will likely pick-up ahead of the arrival of the Umm Slal tanker at the South Hook terminal. * September gas contract up by 0.60 pence to 43.85 p/therm. * In the Dutch gas market, the September gas price at the TTF TTF hub was up by 0.07 euro to 16.17 euros per megawatt hour. * Thomson Reuters (Dusseldorf: TOC.DU - news) analyst view: http://emea1.apps.cp.extranet.thomsonreuters.biz/cms/?pageid=united-kingdom-gas (Reporting by Oleg Vukmanovic; Editing by Edmund Blair)