The administration of President Donald Trump, through the Department of Justice, has appealed to the Supreme Court a ruling by a federal court that deemed most of his global tariff definitions illegal, sparking a legal dispute that could determine the future of his trade agenda.

While the formal appeal was expected and still awaits the court’s acceptance, it is likely to now place the fate of the comprehensive “reciprocal tariffs” imposed by Trump in the hands of the U.S. Supreme Court.

This petition follows a federal appeals court ruling on August 29 that most of the “reciprocal tariffs” imposed by Trump on April 2 were illegal, putting the core of his economic agenda in uncertainty.

The U.S. Court of Appeals for the Federal Circuit ruled 7-4 that Trump exceeded his presidential authority when he imposed these hefty tariffs on nearly all countries.

Late Wednesday, President Donald Trump said the United States might have to “cancel” trade agreements made with the European Union, Japan, South Korea, and others if it loses the tariff case before the Supreme Court.

He warned that losing the case would cause “great suffering” for the United States.

Trump told reporters at the White House that his administration will ask the Supreme Court to overturn a Court of Appeals ruling last week that found many tariffs illegal. He expects his administration to win the case.

He added, “We made a deal with the European Union where they pay us nearly a trillion dollars. You know? They are happy. It’s done. All these deals are done… I think we will have to cancel them.”

This is Trump’s first comment hinting at the possibility of voiding agreements with major trading partners if the Supreme Court upholds last Friday’s ruling.

Trump said canceling tariffs would be costly, although trade experts note that tariffs are paid by importers in the U.S., not companies in the countries of origin.

Economists have warned that tariffs are likely to lead to increased inflation in the United States.

Trump used the International Emergency Economic Powers Act (IEEPA) to impose these hefty tariffs on his trading partners, declaring the U.S. federal deficit with other countries a national emergency.

However, the Court of Appeals said that “tariffs are a core Congressional power,” not a presidential one.

The court added, “The core taxing power of Congress, such as tariffs, is exclusively a legislative power under the Constitution.”

The Court of Appeals decision will not take effect until October 14, giving the Trump administration time to appeal the decision to the Supreme Court.

The Trump administration indicated plans to file an appeal, but questions remain about how quickly it will be submitted.

Attorney General Pam Bondi wrote on her X platform account: “This decision is wrong and undermines the United States’ standing on the global stage.”

She added, “[The Department of Justice] will appeal this decision and continue to fight to restore the President’s lawful authority.”

The Supreme Court is likely to hear the Trump tariff case, according to SCOTUSblog, with a decision possibly issued in summer 2026.