The balance was further tipped toward the U.S. when production rebounded in Libya and Iraq despite political instability, adding to an already oversupplied market, Kilduff added.
OPEC pumped 30.6 million barrels of crude oil per day in September, a jump of 400,000 barrels from August that was driven by the Libyan output rebound, found Platts, a global energy information service.
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OPEC's loss in pricing power is a consequence of not taking U.S. producers more seriously and cutting prices earlier for clients, said Phil Flynn, senior energy market analyst at Price Futures Group.
"Only a year ago, OPEC was still in denial, but with the slowing global economy, they can't laugh off U.S. production anymore," Flynn said.
By 2019, U.S. shale oil production will jump to 9.6 million barrles per day, from 8 million now, according to forecasts from the Energy Information Administration. In comparison, Saudi Arabia currently produces 9.6 million barrels of crude oil a day.