By David Gaffen NEW YORK (Reuters) -Oil prices rose on Thursday, buffeted by concerns about tightened supply as the European Union (EU) mulls a potential ban on Russian oil imports that would further restrict worldwide oil trade. Brent crude futures were up 50 cents to $107.30 a barrel as of 12:59 p.m. ET (1659 GMT), after earlier reaching a high of $109.80 a barrel. U.S. West Texas Intermediate (WTI) crude futures gained 75 cents to $102.94 a barrel, after earlier reaching a high of $105.42. Buyers also reacted to ongoing interruptions in Libya, which is losing more than 550,000 barrels per d…