Trump’s refusal to lift tariffs on steel and aluminum imported from Mexico and Canada has sparked a revolt among Senate Republicans, who are refusing to approve his new North American trade deal until he lifts those tariffs.

Opposition has been especially pronounced among senators representing farm states that have been hurt by Mexico’s retaliatory tariffs on U.S. agricultural products.

Along with more tariffs on Chinese goods, Trump also is considering raising import taxes on automobiles and a variety of products from the E.U. Completing the administrative process involved in levying tariffs on the remaining Chinese goods could take months.

But the president is drawing closer to a choice between a major escalation of his tariff campaign — one that risks enormous economic and political fallout — and a disappointing outcome at the bargaining table.

“We’re in a very different spot than we were just a week ago,” said Carla Hills, who was a U.S. trade representative under President George H.W. Bush. “Tariffs are not a good trade negotiating tool.”