Oil pipelines, pumping rigs, and electrical transmission lines dot the landscape along California’s “Petroleum Highway” (Highway 33) running along the northwestern side of the San Joaquin Valley.
George Rose | Getty Images News | Getty Images

West Texas Intermediate crude futures fell below the key $70 level Monday for the first time in more than a month as OPEC and its allies agreed to raise output, and as the delta Covid variant threatens global demand.

U.S. oil dropped more than 5% to hit a session low of $67.84. The contract is now nearly 12% below its recent high of $76.98 from July 6, which was the highest level in more than six years. International benchmark Brent crude dipped 4.8% to trade at $70.10 per barrel.

The group of 23 nations, known as OPEC+, agreed Sunday to increase production by 400,000 barrels each month beginning in August. The output hike will continue through September 2022, at which point the entirety of the nearly 6 million barrels per day the group is still withholding will be back on the market.

The announcement came after the group’s initial meeting July 1 fell apart amid a disagreement between Saudi Arabia and the United Arab Emirates over the latter’s baseline production quota.

“We view [Sunday’s] deal as supportive to our constructive oil price view with supply increasingly becoming the source of the bullish impulse and evidence of non-OPEC supply shortfalls likely in the coming months,” Goldman Sachs said in a note to clients. The firm pointed to discipline among U.S. producers as providing a floor for oil prices, although it noted that the delta variant could lead to price gyrations in the coming weeks.

OPEC+’s July meeting ending without an agreement sent the oil market into turmoil because it opened the door for the group to potentially disband, with each nation pursuing an independent production policy.

“This was a renewal of OPEC+ vows,” RBC’s Helima Croft said Monday on CNBC’s “Worldwide Exchange.” “We think the market can absolutely absorb the additional 400,000 barrels per month…this is a constructive agreement.”

Energy stocks moved lower on the heels of oil’s decline. The group dipped 4.5%, making it the worst-performing S&P 500 sector. Occidental, Diamondback Energy, Schlumberger and Marathon Oil were among the biggest decliners, each falling more than 6%.

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