The International Emergency Economic Powers Act (IEEPA) is a U.S. federal law from 1977 that lets the president, after declaring a national emergency, regulate trade, impose sanctions, or block assets for national-security or foreign-policy reasons. The recent U.S. Supreme Court decision found the president lacked authority under IEEPA to impose certain tariffs, a ruling that can change how trade measures are used and affect import costs and supply chains relevant to consumers and businesses in Portugal.