Oil prices held on to most gains from the previous session in early trading on Thursday as investors awaited U.S.-China trade talks later in the day.U.S. crude oil on Tuesday hit the lowest level since May, putting prices on pace for the worst performance in seven years as traders factor in a looming surplus and the possiblity of a peace agreement in Ukraine. West Texas Intermediate hit $55.69 per barrel while Brent touched$59.42, the lowest level for the benchmarks since May 5. The U.S. benchmark has lost ...