Oil prices jumped Friday after the Organization of the Petroleum Exporting Countries (OPEC) secured a compromise, albeit modest, agreement that effectively will add about 600,000 b/d to the market, or around 0.5% of global supply.

The Saudi-led cartel of 24 OPEC and non-OPEC members in its 174th meeting in Vienna agreed to adjust the production reductions and raise output by 1 million b/d; global output has been reduced by 1.2 million b/d since the start of 2017.

In reaction, crude oil traded higher on the New York Mercantile Exchange Friday, gaining more than 5%.

OPEC and its allies, which include Russia, will share in the planned increase. Because some members for now cannot raise output, the actual amount to be returned to the market is estimated to be closer to 600,000 b/d than 1 million b/d.

Speaking to reporters after the meeting, Saudi Energy Minister Khalid al-Falih said, “I don’t think anyone should expect an immediate slug to the market.”

However, in reaction to the news, Brent crude climbed nearly 3% early Friday while West Texas Intermediate prices gained around 2.5%.

The agreement still needed official approval by Russia and OPEC’s other allies, who were to meet Saturday. However, Russia, which initially was pushing for higher production, is said to have helped shape the accord.

Member countries “have exceeded the required level of conformity,” which reached 152% in May, OPEC noted.

“The conference analyzed oil market developments since it last met in Vienna at the end of November and reviewed the oil market outlook for the remainder of 2018,” the cartel said. “The conference noted that the oil market situation has further improved over the past six months, with the global economy remaining strong, oil demand relatively robust, albeit with some uncertainties, and with the market rebalancing evidently continuing. Moreover, the return of more stability and more optimism to the industry has been welcomed by all stakeholders.”

OPEC said it was “reaffirming its continued commitment to stable markets, the mutual interest of producing nations, the efficient, economic, and secure supply to consumers, and a fair return on invested capital.” It also noted there is an “overall improvement in market conditions and sentiment, and the return of confidence and investment to the oil industry.”

In May Brent oil prices topped $80/bbl, triggering President Trump to blame OPEC in a series of tweets.

Even without any prodding, Mizuho Energy analyst Paul Sankey on Friday said there was “really no question” that OPEC would increase output,” despite a “rebellion” led by “ultimately toothless” members Iran, Iraq and Venezuela.

“Global stocks are already modestly below ”normal,’ and with no re-ramp from OPEC, we would be drawing hard for the next six months to dangerously tight inventory levels,” Sankey said.

Mizuho’s estimate on global crude oil balances “suggest an increasingly tight scenario for 2019-plus, depending on what happens with non-OPEC/U.S. supply.”

Rystad Energy’s Bjomar Tonhaugen, vice president of oil market research, also weighed in and said it was “essential” that OPEC raise output “to avoid an overly tight market and potential price spike in the second half of this year.” If no consensus had been reached, analysts said Saudi Arabia and Russia likely would have chosen to raise output regardless.

By Rystad’s estimates, global oil products demand in 3Q2018 is expected to increase sequentially by 1.1 million b/d on seasonally higher demand for transportation fuels, increased power generation demand in the Middle East and strong natural gas liquids demand growth in the United States. Demand then is forecast to be flat in the fourth quarter, supported by ongoing global economic expansion.

OPEC’s voluntary supply cuts reduced global supply during 2017, but U.S. tight oil production only accelerated. The impact of the cuts “would have been even bigger” if not for the gains in U.S. oil and liquids production, which grew from October 2016 through 2017 by almost 2 million b/d, according to BP plc chief economist Spencer Dale.

“The scale of the increase in U.S. tight oil meant the impact of the production cuts was increasingly offset as we moved through 2017,” he said earlier this month at the unveiling of BP’s annual Statistical Review of World Energy. The speed and scale of OPEC’s ability to raise and reduce output “mean that it continues to have the ability to smooth temporary disturbances to the oil market,” Dale said. “But the relatively rapid response of U.S. tight oil reinforces the limits on OPEC’s power.”

OPEC is scheduled to convene its next regular meeting on Dec. 3.