US Secretary of State Mike Pompeo said Tuesday that acting Venezuelan President Nicolas Maduro had been preparing to go into exile in Cuba earlier in the day, but was convinced by Russia to stay in Venezuela.

"He had an airplane on the tarmac, he was ready to leave this morning as we understand it, and the Russians indicated that he should stay," he said without mentioning who had provided the information.

"He was headed for Havana."

Read more: How much influence does Cuba have over Venezuela?

The comments came after opposition supporters and government security forces clashed in Caracas in the wake of self-declared President Juan Guaido's call for the military to oust Maduro.

On late Tuesday, Maduro denied any intention of having planned to flee to Cuba.

"Mike Pompeo said that ... Maduro had a plane ready to take him to Cuba but the Russians prevented him from leaving the country. Mister Pompeo, please, this really is a joke," Maduro said.

Embargo threat

Separately, President Donald Trump threatened a "full and complete embargo" and sanctions on Cuba if the country refused to stop providing Venezuela with military support.

"If Cuban Troops and Militia do not immediately CEASE military and other operations for the purpose of causing death and destruction to the Constitution of Venezuela, a full and complete embargo, together with highest-level sanctions, will be placed on the island of Cuba," Trump wrote on Twitter.

"Hopefully, all Cuban soldiers will promptly and peacefully return to their island!"

'Your time is up': Bolton

Earlier, US National Security Adviser John Bolton, a foreign policy hawk, said Guaido enjoyed broad military support, but leaders had hesitated to abandon Maduro for fear of Cuban retaliation.

Read more: Neocon-led US Venezuela policy, rhetoric trigger deja vu effect

He took the unusual step of naming three key Venezuelan government figures that he claimed privately supported Guaido — Defense Minister Vladimir Padrino Lopez, Chief Justice of the Venezuelan Supreme Court Maikel Moreno and Head of the Presidential Guard Ivan Rafael Hernandez Dala.

Shortly after he delivered his statement, Bolton released a tweet warning the three: "Your time is up. This is your last chance."

Propped up by Cuban 'thugs'

Bolton said that despite losing the support of the three men, Maduro was being propped up Russia and Cuba. He was especially critical of Cuban "colectivos," which he called gangs of motorcycle-riding "thugs" that were protecting important installations across Venezuela.

Read more: Venezuela's Guaido calls for uprising in video with troops

Asked if the US was considering a military intervention, Bolton, who is a staunch advocate of the Monroe Doctrine — a policy the US claims guarantees it the right to intervene throughout the Americas to ensure "a completely democratic hemisphere" — said that "all options are on the table."

Asked about the threat of Russian intervention, Bolton said the Trump administration had made it clear to Moscow just how seriously it views the situation. "We expect the Russians not to interfere with what is happening in Venezuela ."

He once again signaled that after Maduro was ousted from power the US would set its sights on Cuba, which Bolton labeled part of the "troika of tyranny" in Latin America, alongside Venezuela and Nicaragua.

amp, js/cmk (AP, AFP, Reuters, dpa)

Watch video 00:34 Guaido: Venezuela in a state of occupation

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