U.S. President Donald Trump has warned that countries reconsidering recently negotiated trade agreements with the United States could face significantly higher tariffs.

Speaking on Monday, Trump cautioned trading partners against what he described as “playing games” with U.S. trade commitments, particularly after the U.S. Supreme Court struck down his use of emergency tariff powers. He indicated that if countries attempt to back away from agreements, his administration would impose steeper duties under alternative trade laws.

The warning follows a major legal setback in which the Supreme Court invalidated the legal foundation for certain emergency tariffs. Despite the ruling, Trump has maintained that the decision clarified executive authority over trade policy and signaled that other statutory tools remain available to enforce tariff measures.

Trump did not specify which countries he was referring to but emphasized that the United States would not tolerate what he characterized as unfair trade practices or renegotiation attempts after agreements have been reached.

The administration has already introduced new global tariff measures under Section 122 of the Trade Act of 1974, which allows temporary import restrictions for up to 150 days. Analysts say Trump’s latest remarks suggest a willingness to escalate trade enforcement using alternative legal mechanisms if necessary.

Economists warn that renewed tariff threats could heighten global trade tensions, disrupt supply chains, and increase costs for businesses and consumers. Supporters argue that strong tariff policies are essential to protecting American manufacturing and ensuring fair trade terms.

Financial markets and foreign governments are expected to closely monitor developments as Washington navigates its next steps following the court ruling.