High Court Blocks Trump Tariffs, Global Markets React to Trade Policy Shift

The Supreme Court struck down President Trump's widespread tariffs Friday, prompting international trading partners to reassess their positions. Trump quickly responded by proposing alternative tariff measures under different legal authority.

International trading partners are closely monitoring Washington’s response after the Supreme Court blocked President Donald Trump’s tariff program, though global financial markets showed measured reactions to Friday’s landmark decision.

The high court’s ruling could potentially upend trade agreements negotiated following Trump’s announcement of extensive tariffs affecting numerous nations in April 2025.

Officials from China’s Commerce Ministry announced they are performing a “comprehensive assessment of” the court’s decision to overturn tariffs that Trump had implemented using the International Emergency Economic Powers Act.

“China urges the United States to lift the unilateral tariffs imposed on trading partners,” a ministry representative stated without providing their name.

Beijing reinforced its position that trade conflicts produce no victors, with the official Xinhua News Agency reporting that a spokesperson described Trump’s previously announced measures as actions that “not only violate international economic and trade rules but also contravene domestic laws of the United States, and are not in the interests of any party.”

Following the Supreme Court ruling, Trump announced plans for a new 10% worldwide tariff using Section 122 of the 1974 Trade Act as legal justification, subsequently raising that figure to 15%.

Nations like China and other Asian countries that faced elevated import taxes on their goods could see some relief under this approach. However, allies including Japan and the United Kingdom might encounter increased tariff rates.

During a CBS News appearance Sunday, U.S. Trade Representative Jamieson Greer emphasized that America intends to honor existing trade agreements and anticipates partners will reciprocate.

“The deals were not premised on whether or not the emergency tariff litigation would rise or fall,” Greer, who serves as Trump’s lead trade negotiator, explained. “I haven’t heard anyone yet come to me and say the deal’s off. They want to see how this plays out.”

South Korea’s trade minister Kim Jung-kwan warned Monday that continued uncertainty could intensify if the Trump administration proceeds with implementing additional tariffs through alternative legal mechanisms.

Kim indicated that South Korean officials have committed to conducting “amicable” conversations with their American counterparts to reduce potential harm to South Korean businesses. Key South Korean export industries including automotive and steel manufacturing already face tariffs under separate trade regulations.

“Given the uncertainty over future U.S. tariff measures, the public and private sectors must work together to strengthen our companies’ export competitiveness and diversify their markets,” Kim stated.

Treasury Secretary Scott Bessent expressed confidence Sunday that trading partners would honor current agreements and predicted tariff collections would remain consistent.

“Tariff revenues will be unchanged this year and will be unchanged in the future,” Bessent told Fox News, referencing Trump’s proposed 15% global tariffs as a substitute measure.

Regarding potential refunds for import taxes already collected under the now-invalidated tariffs, Bessent said the administration would follow judicial guidance.

“It’s out of our hands and we will follow the court’s orders,” he explained.

Early Monday trading showed U.S. market futures declining, with S&P 500 contracts dropping 0.6% and Dow Jones Industrial Average futures falling 0.5%. Oil prices decreased while the dollar lost ground against both the Japanese yen and euro.

Asian markets displayed a different pattern, with most indices posting gains and Hong Kong’s Hang Seng climbing 2.4%.