The US has placed sanctions on Colombia's left-wing president, Gustavo Petro, accusing him of failing to curb drug trafficking.
President Petro has allowed drug cartels to flourish and refused to stop this activity, US Treasury Secretary Scott Bessent said in a statement.
Sanctions have also been imposed on Colombia's Interior Minister Armando Benedetti, as well as Petro's wife and eldest son. They include barring them from accessing assets and properties they may have in the US.
Colombia was once a close ally of Washington's war on drugs, receiving hundreds of millions of dollars annually in military assistance. But Petro and Trump have clashed frequently since Trump's return to power.
Bessent said that since Petro, a former guerrilla, came to power, cocaine production in Colombia has exploded to the highest rate in decades, flooding the United States and poisoning Americans.
He added that Trump was taking strong action and would not tolerate drug trafficking into the US. The Treasury stated Colombia is the world's top exporter of cocaine, posing a significant drug threat to the US.
In a separate statement, the State Department said it would not certify Colombia's counter-narcotics efforts.
Petro has denied the accusations, stating he has been fighting drug trafficking for decades and has helped the US reduce its cocaine consumption.
A complete paradox - but not one step back, and never on our knees, he said.
In recent weeks, the US military has ramped up activity in the southern Caribbean, striking vessels alleged to be carrying drugs.
Last week Trump announced the suspension of payments and subsidies to Colombia, following Petro’s statements condemning US actions as an act of tyranny, accusing them of violating Colombian sovereignty.
Imposing sanctions on a head of state is rare but not unprecedented, with leaders from countries such as Russia, North Korea, and Venezuela having faced similar actions in the past.
