Oil retreated the most in more than two weeks amid worries that OPEC's deal to extend production cutbacks may take U.S. shale activity to a whole new level.
Futures closed 1.5 percent lower in New York. OPEC and partners including Russia last week agreed to keep cutting output through the end of next year. At the same time, North American explorers probably will boost spending by 20 percent in 2018, according to an Evercore ISI survey of industry budget trends.
"It's been a steady climb on the production side here in the U.S., which continues to eat away at OPEC's hopes for balancing this market," John Kilduff, a partner at Again Capital LLC, a New York-based hedge fund, said by telephone. "They are sowing the seeds for the deal unraveling just because the way it's promoting shale output."
The slide comes after oil jumped about a fifth from early September as investors geared up for last week's decision by the Organization of Petroleum Exporting Countries and its allies. The producers will maintain cuts until global supply meets demand, Saudi Arabia's Energy Minister Khalid Al-Falih said. OPEC's output in November dropped to a six-month low, according to a Bloomberg News survey of analysts, oil companies and ship-tracking data.
But the danger is U.S. shale activity may surge, undermining the OPEC reductions. The U.S. oil rig count was already at the highest level since September last week, according to Baker Hughes data released Friday, and U.S. output was at a record high in the latest weekly government statistics.
West Texas Intermediate for January delivery fell 89 cents to settle at $57.47 a barrel on the New York Mercantile Exchange. Total volume traded was about 32 percent below the 100-day average.
Brent for February settlement slid $1.28 to end the session at $62.45 on the London-based ICE Futures Europe exchange, the lowest level in two weeks. The global benchmark crude was at a premium of $4.96 to February WTI.
Pioneer Natural Resources Co., one of the biggest U.S. independent drillers, is planning to raise output to more than 1 million barrels of oil equivalent a day by 2026 from about 300,000 a day this quarter, Chief Financial Officer Richard Dealy reiterated last week at a conference in Singapore.
Citigroup Inc. forecasts that the market will be balanced in 2018 but is bearish for 2019, with a Brent forecast of $49 a barrel as supplies return from OPEC and increase from Brazil and Russia.
A rising dollar also pushed prices lower Monday. The Bloomberg Dollar Spot Index, a gauge of the dollar against 10 major peers, increased as much as 0.5 percent. A stronger greenback typically reduces investors' interest in commodities.
"Oil is really suffering at the moment from having a strong run and momentum trades are getting negatively impacted," Atul Lele, chief investment officer at Nassau, Bahamas-based Deltec International Group, said by telephone. The "slowing U.S. dollar liquidity environment" is also depressing oil prices, he said.
Cushing, Oklahoma, crude stockpiles decreased 2.4 million barrels in the week ended Dec. 1, according to a forecast compiled by Bloomberg. UBS Group AG raised its 2018 Brent oil forecast to $60 from $55 and the bank expects OECD inventories to fall to the five-year average in the third quarter, according to a note. Gunvor Group Ltd. has wooed Noble Group Ltd.'s star gasoline trader to join its expanding U.S. operations as an exodus from the struggling Asian trading house continues amid asset sales and a debt restructuring.