Oil prices eased on Friday and closed the week lower as investors awaited 25% tariffs by the United States on Canada and Mexico, expected on Saturday.

Analysts say tariffs on oil could cause U.S. gasoline prices to rise, because several U.S. refineries rely on processing Canadian oil; if the tariffs were passed completely along to consumers, it could raise gasoline prices by $0.35/gal in parts of the country, Tom Kloza at the Oil Price Information Service said.

The White House said Friday the U.S. will impose 25% tariffs on Canada on Saturday. Oil and uranium markets were already showing signs of anxiety.