House Republican leader Kevin McCarthy also expressed hope that the White House can resolve the immigration dispute with Mexico to avoid the worst of the tariffs.

“I believe that at the end of the day we will get to a solution that solves our problem,” McCarthy said.

Emergency Declaration
There are ways Congress could undercut Trump’s legal authority for the tariffs, but not before Monday when the first 5% round is set to take effect.

If the White House says the justification for the tariffs rests on Trump’s declaration of a national emergency from earlier this year, Congress could revive a resolution of disapproval that already passed both chambers but failed to get enough votes in the House to override Trump’s veto.

If the White House declares a new national emergency, Congress could pass a new resolution of disapproval -- effectively removing the provision Trump would cite to have the power to impose tariffs.

The question is whether Congress would have enough Republicans on board this time to overrule Trump’s veto. That would take roughly 20 Republican senators and 55 Republican representatives would have to stand up to the president -- and their constituents who support him.

Senator Kevin Cramer, a North Dakota Republican, predicted that at least 20 Senate Republicans would oppose Trump on Mexico tariffs.

“You’ve heard of people who are war weary,” Cramer said. “Senate Republicans are tariff weary.”

USMCA Goals
Congress has other ways of exerting pressure. Senate Finance Chairman Chuck Grassley, an Iowa Republican, suggested he won’t begin consideration of the U.S.-Mexico-Canada free trade agreement if the Mexico tariffs are put in place. Grassley used a similar threat to convince the White House to drop tariffs on steel and aluminum from Mexico and Canada earlier this year.

Grassley said while he opposes tariffs as the tool to get there, “my goals on immigration are exactly the same as the president; my goals on USMCA are exactly the same.”