Brent crude oil fell below $115 a barrel on Monday, heading for its first monthly decline this year, as investors weighed the prospect that Europe's debt crisis and a sputtering U.S. economy may slow demand, Reuters reported. Public holidays in the United States and the UK on Monday were limiting trading volume. The U.S. driving season, when gasoline demand usually rises, traditionally starts after Monday's Memorial Day holiday. Brent crude slipped 28 cents to $114.75 a barrel by 1543 GMT, trading within a narrow 76-cent intraday range. U.S. crude dropped 21 cents to $100.38. A stronger dollar can reduce investor demand for dollar-denominated commodities such as oil. Oil traders remained focused on gasoline. Gasoline futures soared on Friday in anticipation of higher demand this summer, but gains were limited as a plunge in U.S. home sales added to worries about the pace of U.S. economic recovery. A U.S. government report last week showed gasoline demand over the previous four weeks was down 2.1 percent on the year and inventories rose more than expected. Nonetheless, some analysts see potential for prices to gain strength. Brent crude is up about 20 percent this year. -- SPA