President Donald Trump said the US will no longer offer subsidies to Colombia, one of the country's closest South American allies.

The US president announced the decision in a Truth Social post on Sunday, labelling Colombia's President Gustavo Petro as "an illegal drug leader" who has "strongly encouraged the massive production of drugs, in big and small fields, all over Colombia".

His comments come after Petro accused the US of committing "murder" when it carried out a military strike on a boat in Colombian territorial waters in September.

The move is the latest in a string of escalating tensions between the US and countries in Latin America, as the US military continues to strike ships in the Caribbean Sea, it alleges carry drugs.

Trump said that because the US offers "large-scale payments and subsidies" and Petro "does nothing" to stop the drug production, the US will no longer offer "payment or subsidies" to Colombia.

According to a government website, the US provided over $740m (£551m) in aid to Colombia in 2023. It is unclear if all of that aid will stop, or when.

In September, for the first time since 1996, the US declared that Colombia had failed to uphold its drug trafficking promises and is ineligible for aid as defined in the Foreign Assistance Act. But the state department included a waiver that allowed Colombia to continue to receive aid.

But following Petro's recent accusation of Americans committing "murder", Trump has escalated matters and says he will halt aid.

Under Petro, cocaine production has reached a record level and the country has failed to reach its coca eradication goals, the state department said in September.

Petro has said the US violated his country's sovereignty, killing a Colombian fisherman with its September attack.

Posting on social media, he said: "The Colombian boat was adrift and had its distress signal up due to an engine failure," when it was struck. He added: "We await explanations from the US government."

"Fisherman Alejandro Carranza had no ties to the drug trade, and his daily activity was fishing. The Colombian boat was adrift and had its distress signal up due to an engine failure."

Alejandro Carranza was reportedly killed on 15 September when US forces allegedly fired on his boat while he was fishing in the Caribbean.

Trump has defended the ongoing boat attacks, saying they are aimed at stemming the flow of drugs from Latin America into the US, but his government has not provided evidence or details about the identities of the vessels or those on board.

UN-appointed human rights experts have described the US strikes as "extrajudicial executions".

The escalation between Trump and Petro comes on the heels of another attack on a ship in the Caribbean sea.

That attack, which happened on Thursday, is at least the sixth US strike on ships in the Caribbean Sea in recent weeks. At least 27 people were killed in the prior five boat strikes in the waters off Venezuela, according to figures released by the US administration.

The Thursday attack, on a submarine, is the first time survivors have been reported, though the attack also killed two people.

Trump said US intelligence confirmed the vessel was "loaded up with mostly Fentanyl, and other illegal narcotics".

The US president said two people who survived the submarine attack would be returned to their countries of origin, Ecuador and Colombia.

They were transferred to a US Navy ship, a source familiar with the matter told CBS News, the BBC's US partner.

In recent weeks, Trump has ramped up threats against Venezuela's leadership over claims that the country is sending drugs to the US. Venezuelan President Nicolás Maduro has accused Trump of trying to make the South American nation "an American colony".

Trump earlier told reporters that he had authorised the CIA to conduct covert operations in Venezuela, and that he was considering launching attacks on Venezuelan soil.