LONDON (Reuters) - Motorists around the world have been paying more for their gasoline over the past month as falling U.S. stocks of the motor fuel have helped to drive up global oil prices.A woman spills petrol after filling her car at a petrol station in Tehran in this file photo, March 1, 2007. Motorists around the world have been paying more for their gasoline over the past month as falling U.S. stocks of the motor fuel have helped to drive up global oil prices. REUTERS/Caren Firouz