A federal appeals court struck down most of President Trump’s sweeping tariffs Friday, saying they have no legal basis. The decision could undo many of Trump’s tariffs from “Liberation Day” in April, as well as earlier tariffs against Canada, Mexico and China. In its ruling, the appeals court called levying tariffs “a core Congressional power,” but the White House had argued the president has authority to impose tariffs without Congress based on the 1977 International Emergency Economic Powers Act. The tariffs will remain in effect until October, giving the Trump administration time to bring the case to the Supreme Court. The decision encompasses two different cases that had challenged the tariffs: one brought by a group of U.S. states, led by Oregon, and the other brought by a group of businesses. “It’s a sweeping decision that unequivocally rebukes President Trump’s idea that he can impose tariffs on American consumers on his own without the approval of the Congress,” says attorney Neal Katyal, who represents the businesses that initiated the tariff lawsuit. Oregon Attorney General Dan Rayfield says his state challenged the tariffs because of their economic impact since “about 70% to 80%” of the costs are paid by U.S. consumers. “I really think we have to start calling them regressive taxes,” Rayfield says.