US crude oil stockpiles increased more than 10 million barrels last week, the highest since March 2021, thanks to releases from the Strategic Petroleum Reserve and lower activity at refineries.

In contrast to analysts' predictions in a Reuters poll for a 3.6 million-barrel reduction, crude inventories (USOILC=ECI) rose by 10.2 million barrels in the week ended Dec. 9 to 424.1 million barrels.

The crude stockpile amount was adjusted by 2.26 million barrels per day (bpd). The change was due to exports, which were significantly lower in the US Gulf last week than the EIA stated, according to Kpler analyst Matt Smith.

There was a sharp crude build, which came as recession threatens economies in the United States and Europe, worrying markets about the demand for crude oil and petroleum products.

The EIA reported that while stocks at the Cushing, Oklahoma, delivery hub for US futures (USOICC=ECI) increased by 426,000 barrels, SPR crude inventories decreased by 4.7 million barrels in the week to 382.3 million, its lowest level since January 1984.

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The Keystone pipeline shutdown last week, which ferries about 620,000 bpd of crude from Canada to the United States, is expected to hit inventories at Cushing and Gulf Coast.

Refinery crude runs (USOICR=ECI) decreased by 459,000 bpd last week, according to the EIA, resulting in a 3.3 percentage point drop in overall utilization rates (USOIRU=ECI) to 92.2% of total capacity.

"(Refiners) were just making too much product and had to pull back on the refiner utilization rate and that's going to tempt builds," said Bob Yawger, director of energy futures at Mizuho.

The EIA said that US gasoline stocks (USOILG=ECI) increased by 4.5 million barrels in the past week to 223.6 million barrels, exceeding forecasts for a 2.7 million-barrel increase. ​

The data also revealed that distillate stockpiles (USOILD=ECI), which comprise diesel and heating oil, increased by 1.4 million barrels in the week to 120.2 million barrels, versus projections for a 2.5 million-barrel increase. ​

Net US crude imports (USOICI=ECI) fell last week by 31,000 bpd, the EIA said.

After the data was released, crude futures continued their upward trend from earlier in the day. As of 10:45 a.m. EST, U.S. crude rose $1.16, or 1.6%, to $76.54 per barrel, while Brent crude increased $1.23, or 1.5%, to $81.92 per barrel. ​