President Donald Trump expressed intense disapproval following the U.S. Supreme Court’s decision that he lacks the authority to impose tariffs on imports unilaterally. He criticized the justices individually and pledged to utilize other legislation to continue his international trade strategies.

The Supreme Court’s significant 6-3 decision on Friday disrupted the influence Trump and his trade representatives previously exerted over both allied and adversarial nations during negotiations aimed at altering diplomatic ties and global market dynamics.

This ruling cast doubt on numerous trade agreements brokered by his team recently, which were negotiated under the looming threat of steep tariffs.

The decision also propelled all three major U.S. stock indexes to their highest points in weeks. It further raised questions about the future of the $175 billion Trump accumulated from U.S. importers due to what the court identified as a misinterpretation of the law.

“I’m deeply disappointed in certain court members, utterly disappointed for failing to do what’s best for our nation,” Trump declared to reporters at the White House, asserting that foreign nations were celebrating the verdict and “rejoicing openly.”

He suggested, without offering proof, that corruption influenced the majority opinion authored by Chief Justice John Roberts: “Their actions are very unpatriotic and betray our Constitution. I believe the court has been influenced by foreign interests and a political agenda far less significant than anyone could imagine.”

Since returning to the White House 13 months ago, Trump has said he had what the court summarised as the “extraordinary power to unilaterally impose tariffs of unlimited amount, duration, and scope.”

Citing a national emergency, he said the International Emergency Economic Powers Act (IEEPA) meant he could set tariffs at any rate he chose.

The court’s ruling was blunt: Trump has not proved that the president has this power, and exceeded his authority. A tariff levied on US importers is a tax ‌like any other, the court said, and the Constitution reserves the power to “lay and collect Taxes, Duties, Imposts and Excises” to Congress.

In response, an angry Trump said he would invoke other laws to collect tariffs, and announced a blanket 10 per cent tariff on imports from all other countries, on top of any existing non-IEEPA tariff.

In doing so, he became the first president to invoke Section 122 of the Trade Act of 1974, in which Congress said the president could levy tariffs of up to 15 per cent for up to 150 days to fix “fundamental ⁠international payments problems”.

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