United States Secretary of War Pete Hegseth said he has every authorisation needed for military strikes on vessels just off the coast of Venezuela, allegedly carrying illegal drugs.

Hegseth was speaking in a Fox News interview broadcast on Sunday. The United States killed four people in a strike in the Caribbean Sea on Friday, at least the fourth such attack in recent weeks.

“We have every authorisation needed. These are designated as foreign terrorist organisations,” Hegseth said in an interview on Fox News’ ‘The Sunday Briefing’.

He did not provide more details about the authorisation.

Washington has cited the US Constitution, war powers, designation of drug cartels as foreign terrorist organisations, the right to self-defence and international law on unlawful combatants as the legal basis for the strikes.

Legal experts and some lawmakers argue that using military force in international waters against alleged criminals bypasses due process, violates law enforcement norms, lacks a clear legal foundation under US and international law and is not justified by the cartels’ terrorist designation.

Hegseth and US President Donald Trump have not provided evidence for claims that the targeted boats were carrying drugs. Trump told Congress last week that he had determined the US to be in “a non-international armed conflict” with drug cartels, without providing any new legal rationale.

Critics say the boat strikes are a further effort by Trump to test the scope of his presidential powers. Legal experts have questioned why the military is carrying out these attacks rather than the US Coast Guard, the country’s maritime law agency.

“If you’re in our hemisphere, if you’re in the Caribbean, if you’re north of Venezuela and you want to traffic drugs to the United States, you are a legitimate target of the United States military,” Hegseth said.

Trump said on Sunday that the US military buildup in the Caribbean had halted drug trafficking from South America.

“There’s no drugs coming into the water. And we’ll look at what phase two is,” he told reporters at the White House.

Russian Foreign Minister Sergei Lavrov on Sunday told his Venezuelan counterpart that the country condemns the US strikes and is concerned about the dangers of potential escalation in the Caribbean.