The US president has branded the government in Caracas a "terrorist organization" and imposed an oil blockade on the country

President Donald Trump has imposed an oil blockade on Venezuela, redirecting a massive US naval armada in the Caribbean from operations against alleged "narcoterrorists" to intercepting "sanctioned tankers" entering and leaving the country.

Trump announced the move in a Truth Social post on Tuesday, describing it as "a total and complete blockade of all sanctioned oil tankers going into, and out of, Venezuela."

"Venezuela is completely surrounded by the largest armada ever assembled in the history of South America. It will only get bigger, and the shock to them will be like nothing they have ever seen before - until such time as they return to the United States of America all of the oil, land, and other assets that they previously stole from us," Trump added.

The announcement follows the recent US seizure of a large sanctioned oil tanker off the Venezuelan coast, a rare direct military action against Venezuelan oil exports, which the administration says was part of an ongoing crackdown.

Trump has also branded the government of President Nicolas Maduro a "Foreign Terrorist Organization," claiming that its oil profits fuel criminal networks and undermine regional security.

The move comes amid a US naval buildup in the Caribbean and Trump's threats to carry out strikes against alleged "narcoterrorists" on Venezuelan soil. Since September, the US military has killed more than 80 people in attacks on alleged cartel boats, which Trump claimed were being used by the Venezuelan government to "flood" America with narcotics.

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Venezuela has denied any involvement in drug trafficking and said the strikes were part of a "colonialist" plan to topple Maduro and plunder the country's natural resources. Caracas also accused the US of "state piracy" and has vowed to defend its territory and natural wealth.