U.S. crude oil stockpiles rose by more than 10 MMbbl last week, the most since March 2021, buoyed by releases from the Strategic Petroleum Reserve (SPR) and as refiners reduced activity.

Crude inventories increased by 10.2 MMbbl in the week ended Dec. 9 to 424.1 MMbbl, compared with analysts' expectations in a Reuters poll for a 3.6 MMbbl drop.

The crude stockpile figure included a 2.26 MMbbl/d adjustment. Kpler analyst Matt Smith attributed the adjustment to exports which were considerably lower on the U.S. Gulf last week than the Energy Information Administration (EIA) reported.

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

SPR crude inventories fell by 4.7 MMbbl in the week to 382.3 MMbbl, their lowest since January 1984, while stocks at the Cushing, Oklahoma, delivery hub for U.S. futures rose by 426,000 bbl, the EIA said.

Last week's shutdown of the Keystone pipeline, which ferries about 620,000 bbl/d of crude from Canada to the United States, is expected to hit inventories at Cushing and Gulf Coast.

Refinery crude runs fell by 459,000 bbl/d last week, the EIA said, reducing overall utilization rates by 3.3 percentage points 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.

U.S. gasoline stocks rose by 4.5 MMbbl in the week to 223.6 MMbbl, the EIA said, compared with expectations for a 2.7 MMbbl rise.​

Similarly, distillate stockpiles, which include diesel and heating oil, rose by 1.4 MMbbl in the week to 120.2 MMbbl, the EIA data showed, versus expectations for a 2.5 MMbbl rise.

Net U.S. crude imports fell last week by 31,000 bbl/d, the EIA said.

Crude futures, already trading higher during the day, extended gains after the data release. Brent crude was up $1.23, or 1.5%, to $81.92 a barrel, while U.S. crude gained $1.16, or 1.6%, to $76.54 a barrel as of 10:45 a.m. EST.