“We are certainly looking at land now, because we’ve got the sea very well under control,” Trump told reporters in the Oval Office, when asked if he was weighing strikes on land.

But Trump declined to confirm a New York Times report that he had secretly authorised the CIA to conduct covert action in Venezuela against the administration of President Nicolas Maduro.

Asked if he had given the CIA authority to “take out” Maduro, Trump replied: “That’s a ridiculous question for me to be given. Not really a ridiculous question, but wouldn’t it be a ridiculous question for me to answer?”

Trump said on Tuesday that another strike on boats allegedly transporting drugs from Venezuela had killed six “narcoterrorists.”

At least 27 people have been killed so far in such attacks. Experts question the legality of using lethal force in foreign or international waters against suspects who have not been intercepted or questioned.

Colombia’s President Gustavo Petro has said he believes some of those killed were Colombian.