Oil prices held above $91 per barrel in light trading Monday, the first day after the Christmas break. An unexpectedly large drop in U.S. supplies pushed crude prices above that threshold last week. Any chance that prices would retreat again disappeared over the weekend after OPEC ministers signaled oil production would not be bumped up, AP reported. Benchmark oil for February delivery fell 32 cents to $91.19 per barrel on the New York Mercantile Exchange. Prices hit $90 for the first time in two years this month with demand starting to tick higher. And more investment banks see a return to $100-per-barrel oil next year. The Organization of Petroleum Exporting Countries, which accounts for aboutt 40 percent of global crude production, influences oil prices through production quotas. While higher prices means stronger revenue, OPEC is also aware that an overheated oil market would stunt economic growth and eventually cut energy demand. Though on the rise, the amount of oil being consumed remains far below the boom markets of just a few years ago. U.S. petroleum demand has increased year-over-year, but it has not come close to the eight years that preceded the recession, according to government figures released this month. In London, Brent crude lost 2 cents to $93.75 a barrel on the ICE Futures exchange.