Caption Close Oil topped $70 a barrel in London for the first time in three years as production cuts by OPEC and rising demand whittle away a global surplus. Brent crude futures, used in the pricing of more than half the world's oil, rose as much as 1.2 percent to the highest since Dec. 4, 2014. Prices rallied after the longest stretch of declines in U.S. inventories during winter in a decade. Oil's rally shows that the Organization of Petroleum Exporting Countries and its allies are succeeding in clearing the glut triggered by the growth of U.S. shale oil. Prices have also been supported by concerns that supply disruptions could stem from rising political tensions in OPEC members Iran and Venezuela.