US President Donald Trump said he would raise tariffs on Colombia and stop all payments to it, escalating a feud that stems from the US military's strikes on vessels allegedly transporting drugs in the region.
Secretary of War Pete Hegseth said US forces had attacked a vessel associated with a Colombian rebel group.
Colombian President Gustavo Petro said the boat belonged to a "humble family," not a rebel group.
Mr Trump's latest comments marked a new low in relations between the US and Colombia, which Mr Trump accuses of being complicit in the illicit drug trade.
"They don't have a fight against drugs - they make drugs," Mr Trump told reporters on board Air Force One.
Mr Petro has objected to the US military's strikes against vessels in the Caribbean, which have killed dozens of people and inflamed tensions in the region.
Many legal experts and human rights activists have also condemned the series of military actions.
Mr Trump said US financial aid would be cut off to the country and details about the new tariffs would be unveiled today.
"I'm stopping all payments to Colombia," he said.
It was not clear what funding support Mr Trump was referring to.
Colombia was once among the largest recipients of US aid in the Western Hemisphere, but the flow of money was suddenly curtailed this year by the shuttering of USAID, the US government's humanitarian assistance arm.
Colombia currently pays 10% tariffs on most imports to the United States, the baseline level Mr Trump has imposed on many countries.
Colombia's foreign ministry vowed to seek international support in defence of Mr Petro and the country's autonomy.
"These accusations represent an extremely serious act and undermine the dignity of the president of Colombians," it said in a statement.
Mr Hegseth wrote on X that the Pentagon had destroyed a vessel and killed three people on Friday "in the USSOUTHCOM area of responsibility," which includes the Caribbean.
He said the ship was affiliated with the leftist rebel group National Liberation Army and was involved in illicit narcotics smuggling, without offering evidence to back the claim.
The Pentagon said it had nothing to add beyond Mr Hegseth's initial post.
Mr Petro condemned the strike, saying the boat belonged to a "humble family," not the National Liberation Army. He also hit back at Mr Trump's remarks.
"Mr Trump, Colombia has never been rude to the United States ... but you are rude and ignorant to Colombia," Mr Petro said on X.
"Since I am not a businessman, I am even less a drug trafficker. There is no greed in my heart," he added.
Earlier this month, Mr Petro said one of the strikes hit a Colombian vessel, an allegation the Trump administration denied.
Last month, the United States revoked Mr Petro's visa after he joined a pro-Palestinian demonstration in New York and urged US soldiers to disobey Mr Trump's orders.
Colombia is fighting its own longstanding drug problems.
Last year, Mr Petro pledged to tame coca-growing regions in the country with massive social and military intervention, but the strategy has brought little success.
In September, Mr Trump designated countries such as Afghanistan, Bolivia, Burma, Colombia and Venezuela among those the United States believes to have "failed demonstrably" in upholding counternarcotics agreements during the past year.
