Washington (AFP) – President Donald Trump said a US new strike on an alleged drug trafficking boat from Venezuela killed three people Monday, as the South American country's president Nicolas Maduro vowed to resist Washington's "aggression."

Trump's administration has faced questions over the legality of deadly military strikes on suspected drug boats since the first such attack earlier this month which killed 11 people.

The fresh attack also comes amid spiraling tensions in the Caribbean as a large US naval build-up sparks speculation that Washington may be seeking regime change in Caracas.

Trump posted a video of a boat bobbing in the sea before exploding in a ball of orange flame as he announced the strike on social media, adding that it resulted in "3 male terrorists killed in action."

"The Strike occurred while these confirmed narcoterrorists from Venezuela were in International Waters transporting illegal narcotics (A DEADLY WEAPON POISONING AMERICANS!) headed to the U.S," he said.

The strikes have raised questions about whether they are within international law or effectively amount to extrajuducial killings, but Trump insisted the United States was confident that the dead men were traffickers.

"We have proof," Trump told reporters in the Oval Office.

"All you have to do is look at the cargo that was, like, it's spattered all over the ocean. Big bags of cocaine and fentanyl all over the place."

Tensions between longtime foes the United States and Venezuela reached new heights in recent weeks after Trump dispatched eight warships to waters near Venezuela to pressure Maduro.

The United States accuses the leftist of heading a cocaine trafficking cartel and recently doubled its bounty for his capture to $50 million. Much of the international community rejected his July 2024 re-election, with the opposition claiming widespread fraud.

Maduro hit back on Monday, branding US Secretary of State Marco Rubio the "lord of death and war" over his tough rhetoric on Latin American cartels.

Referring to the US naval build-up and the earlier boat attack, Maduro told reporters that Caracas would "fully" exercise its "legitimate right to defend itself."

Maduro often accuses the United States of attempting regime change in his country.

Speculation has been swirling that the Trump administration could be preparing targeted strikes against Latin American drug cartels, including in Venezuela.

Trump refused to deny it was a possibility on Sunday.

"We'll see what happens," Trump told reporters when asked if strikes on the Venezuelan mainland were possible. "Venezuela is sending us their gang members, their drug dealers and drugs. It's not acceptable."

Earlier this month Washington dramatically upped the ante by blowing up a speedboat with 11 people on board that it claimed was smuggling drugs from Venezuela.

In an interview with Fox News during a visit to Jerusalem on Monday, Rubio defended the attack on the boat traveling in international waters, amid questions over its legality.

"We have 100 percent fidelity and certainty that that boat was involved in that trafficking of those drugs," Rubio said.

Maduro said communications with the Trump administration had broken down over the US "aggression," adding his country would "confront it."

He leveled much of the blame at the hawkish Rubio, the son of Cuban immigrants to the United States who has been a vehement critic of left-wing authoritarian governments in Latin America.

Although most of the cartels on the terrorism list are Mexican, Washington has focused its attacks on Venezuela.

Maduro said the "bomb threats" had caused a complete collapse in relations between the two countries, which broke off diplomatic ties in 2019.

In the face of the US pressure, he has deployed 25,000 troops to Venezuela's border with Colombia, a transit point on the Latin American drug trafficking route, and along the Caribbean coast.

Thousands of people have also joined a civilian militia intended as backup for the military.

Over the weekend, they thronged training camps where they learned to handle and fire weapons.

"If they (the United States) try to attack the homeland, the entire population will defend it!" said Jenny Rojas, a 54-year-old lawyer who was among the recruits.