U.S. Secretary of State Mike Pompeo claims that Venezuelan President Nicolas Maduro was ready to leave his troubled country for exile in Cuba but was persuaded by Russia to remain.

"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," Pompeo told CNN on April 30.

Pompeo added that Washington had been told in recent weeks by "senior leaders" within the Venezuelan government that they would defect in the event of an uprising.

Pompeo did not identify the people or speak further on details of potential defections.

Pompeo also did not answer directly when asked by reporters if the United States would ensure Maduro's safety if the embattled socialist president fled to Cuba, saying only that the Venezuelan leader was aware of U.S. "expectations."

The reports come as tensions reached new heights in the South American country.

Violence flared as U.S.-backed opposition leader Juan Guaido urged the military to help oust Maduro from the presidency.

Thousands of Venezuelans came out in the capital, Caracas, early on April 30 to support what Guaido called the "final phase" of a campaign to assume power as his supporters rallied outside an air base.

Officials in Maduro's government denounced Guaido's actions as an attempted coup and said they retained the support of the military.

Guaido, whose claim as interim president is backed by the United States and more than 50 other countries, appeared in a video recorded next to the La Carlota air base surrounded by several heavily armed soldiers backed by armored vehicles.

U.S. President Donald Trump tweeted that Washington stands with the "People of Venezuela and their Freedom." Vice President Mike Pence said on Twitter that "America will stand with you until freedom & democracy are restored."

Trump also threatened a "full and complete embargo" and sanctions on Cuba if its troops did not cease operations in Venezuela after U.S. national security adviser John Bolton alleged that Cuban troops were keeping Maduro in power.

Bolton said it was a "very delicate moment" for Venezuela.

"If this effort fails, they will sink into a dictatorship from which there are very few possible alternatives," Bolton added.

Russia, Iran, China, and Cuba are among countries supporting Maduro, who started a second term in January following a May 2018 election marred by an opposition boycott and claims of vote-rigging, leading to mass street protests.

Russia, which has substantial economic ties to Maduro's government, in March sent planes carrying nearly 100 military personnel the U.S. government believes included special forces and cybersecurity experts to Venezuela.

Russian President Vladimir Putin discussed the situation in Venezuela, among other topics, with members of his Security Council, Kremlin spokesman Dmitry Peskov said.

With reporting by AFP, Reuters, dpa, and TASS