While oil prices are down after OPEC refused to curtail production, it won't have a big impact on output from U.S. shale producers, at least for the near term, IHS' Dan Yergin told CNBC on Monday.
"There's a lot of momentum in the system so I think you don't really see the big impact of it in terms of output until the second half of the year," Yergin, the global information and analytics firm's vice chairman, said in an interview with "Street Signs."
That said, every company is now looking at what it can slow down, cut or postpone, he said. "The knives are already out."
U.S. crude settled up $2.85, or 4.3 percent, at $69 a barrel on Monday, rebounding from a five-year low.
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Benchmark Brent crude was last up over $72 per barrel. It had fallen by almost $3 earlier to shy of $64, a low since July 2009.