All else equal, this would increase gasoline prices, which in most of the country have averaged $3 per gallon for the past year amid historically low levels of petroleum inventories (see chart). But Trump wants lower gasoline prices, which is why if the oil tariffs come at all, they will likely start slowly.

U.S. President Donald Trump said on Friday he expects his administration to impose tariffs related to oil and gas around Feb. 18 and it could lower levies on some Canadian crude. He did not name a specific country to which the new tariffs would apply or specify any more details about the plans.