The “shock therapy” of a steep drop in crude prices, which have fallen to a five-year low, is no solution for OPEC’s loss of market share to U.S. shale producers, Iran’s Oil Minister Bijan Namdar Zanganeh said. U.S. benchmark West Texas Intermediate crude declined 10 percent after the Organization of Petroleum Exporting Countries decided on Nov. 27 to keep its production target unchanged at 30 million barrels a day. Prices at this lower level are no guarantee of a significant reduction in U.S. shale output, Zanganeh said in an interview in Tehran on Nov. 28, after arriving from the OPEC meeting in Vienna. “High prices are a disadvantage to OPEC’s market share,” he said. “If you want to increase your share, you have to reduce prices, but you can’t do it through ‘shock therapy’ over the course of three months if you want to change everything.” OPEC, which supplies about 40 percent of the world’s oil, resisted calls from members including Venezuela and Iran to reduce its collective output to stem falling prices. U.S. production, driven by a boom in fracking for shale oil, has risen to the highest level in three decades, adding to a global surplus that Venezuela estimated last week at 2 million barrels a day. Demand for OPEC’s crude will shrink as U.S. supply expands, eroding the group’s share of the global market to the smallest in more than 25 years, its own forecasts showed.