The Supreme Court on Friday ruled that President Donald Trump violated federal law when he unilaterally imposed sweeping tariffs across the globe, a striking loss for the White House on an issue that has been central to the president’s foreign policy and economic agenda.

The decision is arguably the most important loss the second Trump administration has sustained at the conservative Supreme Court, which last year repeatedly sided with the president in a series of emergency rulings on immigration, the firing of the leaders of independent agencies and deep cuts to government spending.

Chief Justice John Roberts wrote the majority opinion and the court agreed 6-3 that the tariffs exceeded the law.

“The president asserts the extraordinary power to unilaterally impose tariffs of unlimited amount, duration, and scope,” Roberts wrote for the court.

“In light of the breadth, history, and constitutional context of that asserted authority, he must identify clear congressional authorization to exercise it.”

The emergency authority Trump attempted to rely on, the court said, “falls short.”

This story is breaking and will be updated.