President Donald Trump’s trade war faces a crucial test as a federal appeals court hears a challenge to his use of emergency powers to impose sweeping tariffs on imports.

Trump's sweeping tariff agenda is at the center of a lawsuit at a federal appeals court, as the legal battle looks likely to go to the Supreme Court.

“IEEPA nowhere mentions tariffs, duties, imposts, or taxes, and no other President in the statute’s nearly 50-year history has claimed that it authorizes tariffs,” the companies added in a filing with the appeals court.