NEW YORK (Reuters) - Many U.S. oil refiners rely heavily on imported crude because their facilities are configured to run heavier grades, such as those coming in from Mexico and Canada. 

Refiners are awaiting clarity and preparing for U.S. President Donald Trump's threatened tariffs on crude imports from Canada and Mexico.

Trump said on Friday that he would lower threatened tariffs on Canadian oil to 10% and that tariffs on oil and gas are likely to take effect on Feb. 18.

A tariff on oil imports could drive up the cost of crude, pushing refiners to cut the amount of oil their facilities process. Refineries in the Midwest process about 70% of the 4 million barrels per day (bpd) of crude imported from Canada.

Phillips 66 said there could be production cuts in the U.S. Midwest and Rocky Mountain region where alternative crude supplies are limited if tariffs take effect.

The refiner expects the 457,000 bpd of Mexican crude that comes into the U.S. could be displaced and move to Europe or Asia.

"We would expect to see the heavy crudes firm a bit just on the inefficiency of logistics," said Brian Mandell, executive vice president of marketing and commercial at Phillips 66. "As the year goes on and OPEC puts more barrels back onto the market, we would expect those differentials to widen back out."

Phillips 66, along with HF Sinclair and Par Pacific Holdings ( PARR ), has elevated exposure to Canadian crude, data from TD Cowen shows.

"Our commercial and optimization teams have been working hard to develop every possible scenario we can think of and how we would respond," said Gary Simmons, chief operating officer of Valero Energy ( VLO ), during a  call with analysts on Thursday. "You might see at a 10% change in throughput. A lot depends on how far it goes and how deep you have to back off on some of those heavy barrels." 

Valero is the second-largest U.S. refiner by capacity.

HF Sinclair, Par Pacific ( PARR ) and Marathon did not immediately respond to requests for comment.

Below is the latest available data on the volume of crude oil top U.S. independent refiners imported from Canada and Mexico in November 2024.

Refiner Canada (thousands of Mexico (thousands of

barrels) barrels)

HF 5,060  

Sinclair

Phillips 14,481 497

66

Par 1,356  

Pacific

Marathon 15,535 1,488

Valero 1,147 6,599

Source: Data from U.S. Energy Information Administration

Note: Data released on Jan 31, 2025