Automakers thought Canada was getting a trade deal. Then tariffs doubled.

Even before the talks blew up, Detroit auto executives had been pressing their case to the administration that Trump's gauntlet of tariffs over the past 18 months had left them in a worse position than Asian and European rivals.

Tariffs on imports from those markets stand at 15%, thanks to separate trade deals struck last year with those partners. Yet Trump's levies have remained 25% on Detroit automakers’ biggest trading partners, Mexico and Canada, with some relief on the value of their U.S. content.

The administration also has floated the idea of requiring imported cars from Canada and Mexico to have half their content come from U.S.-made parts in order to qualify for lower tariffs, people familiar with the plan have said. Imports from Asia and Europe face no such U.S. or North American content requirements.

This week, auto industry lobbyists said they are puzzled about why Washington is effectively boxing out Canada, a country whose automotive supply chain is deeply intertwined with the U.S.