A federal court has blocked Donald Trump’s broad use of tariffs, ruling that the Constitution grants Congress - not the president - authority to regulate foreign commerce. The decision challenges Trump's use of the 1977 International Emergency Economic Powers Act (IEEPA) to impose sweeping import taxes, a cornerstone of his ‘America First’ agenda. Two lawsuits, one by small businesses and another by a coalition of US states, sparked the ruling. The court also blocked tariffs on China, Mexico, and Canada, imposed under immigration and drug control claims. However, tariffs on specific goods like steel and cars were not addressed. Markets responded positively, with global stocks rising and the dollar strengthening. If the ruling is upheld, affected businesses may receive tariff refunds with interest. Legal experts suggest the decision may constrain executive power over trade, sending a strong constitutional message. The White House has vowed to appeal, calling the ruling a judicial overreach. In another development, the Trump administration has asked the supreme court to overturn a judge’s ban on deporting migrants without giving them a chance to seek legal relief: see Breaking news: the ban on tariffs has been temporarily paused by an appeal court.