Trump Threatens 50 Percent Tariffs On Iran Arms Supplies. His Legal Path Is Murky.

President Donald Trump on Wednesday threatened 50 percent tariffs on any country that supplies military weapons to Iran, though it’s not clear he has the legal authority to do so.

“A Country supplying Military Weapons to Iran will be immediately tariffed, on any and all goods sold to the United States of America, 50%, effective immediately. There will be no exclusions or exemptions!” Trump wrote in a post on Truth Social.

While the president previously wielded tariffs to pressure other countries to bend to his will, the Supreme Court in February took away the main legal justification — a 1977 emergency law — he had used to slap those levies on countries at will.

The tariff tools he has left at his disposal are more limited and cumbersome, requiring more specific justifications and more thorough investigations before tariffs can be imposed.

The White House did not immediately respond to a request for comment about what legal authority the president plans to use to enforce his threat.

Trump could, for instance, try to use Section 338 of the Tariff Act of 1930, which allows the president to impose tariffs of up to 50 percent. However, that statue is supposed to be used to combat foreign discriminatory trade practices or restrictions against U.S. goods — a legal stretch in the case of weapons sales.

His most legally durable tariff option, based on investigations into dozens of countries’ unfair trade practices, is still in the works. But he could use a previous investigation into China’s trade practices conducted in his first term to potentially justify tariffs on Beijing, specifically.

Beijing supplies Tehran with dual-use items including drones and spare parts that the Iranian regime weaponizes for its military forces. Iran was close to sealing a deal to buy Chinese-produced ship-killer cruise missiles, Reuters reported last month.

However, the threat of new sanctions linked to China’s trade with Tehran could roil plans for a long-anticipated summit between Trump and Chinese leader Xi Jinping in Beijing next month. The Chinese embassy in Washington didn’t immediately respond to a request for comment.

Trump’s post threatening new tariffs comes just hours after he announced a two-week ceasefire with Iran that could pave a path for an end to war in the Middle East.

The president, in a post on Truth Social overnight, called it a “big day for World Peace!”

Daniel Desrochers, Phelim Kine and Ari Hawkins contributed to this report.