Oil held near its highest in nearly three years on Wednesday, supported by political tension in the Middle East, although evidence of rising U.S. crude supply acted as a counterbalance.  Brent crude has gained 5.7 percent this week, rising to $71.34 a barrel on Tuesday, the highest since late 2014, although the price has since fallen back and was $70.98 a barrel by 0907 GMT LCOc1, down 6 cents.  U.S. crude futures CLc1 were at $65.55 a barrel, up 4 cents on the day.  The United States and its allies are considering air strikes against Syrian President Bashar al-Assad’s forces following a suspected poison gas attack last weekend. Pan-European air traffic control agency Eurocontrol said late on Tuesday that air-to-ground and/or cruise missiles could be used within the next 72 hours, warning of intermittent disruption of radio navigation equipment.