US President Donald Trump has ordered 'a total and complete' blockade of all sanctioned oil tankers entering and leaving Venezuela - a move denounced by Caracas as 'warmongering threats'.

Trump wrote that Venezuelan President Nicolás Maduro's government had been designated a foreign terrorist organisation (FTO), which had also engaged in 'Drug Smuggling, and Human Trafficking'.

His remarks come after the US seized an oil tanker off the coast of Venezuela last week, a significant action in light of the South American nation's reliance on oil.

The US has also recently conducted deadly strikes on alleged Venezuelan drug-smuggling boats and has significantly built up its naval presence nearby.

Trump's post did not give further detail on how the wide-ranging blockade on sanctioned oil tankers would be enforced. As of last week, more than 30 of the 80 ships in Venezuelan waters or approaching the country were under US sanctions, according to data compiled by TankerTrackers.com.

Multiple new US sanctions on ships said to be carrying Venezuelan oil were issued after the tanker was seized. Sanctions were also placed on some of President Maduro's relatives and on businesses associated with what the US called his illegitimate regime.

In his Truth Social post, Trump wrote that Venezuela was 'completely surrounded by the largest Armada ever assembled in the History of South America' and that it would 'only get bigger' and 'be like nothing they have ever seen before'.

Trump accused Maduro's government of using 'stolen' oil to finance drug-related activities.

The US has escalated its military actions against alleged drug trafficking from Venezuela, but has not provided public evidence linking those vessels to specific drug shipments.

In response, Venezuela accused the US of trying to steal its oil resources.

Venezuelan officials have condemned the US military's actions, arguing they threaten national sovereignty, as the country struggles amidst heavy international sanctions and economic turmoil.

In a related note, Congressman Joaquin Castro remarked that Trump's blockade constitutes an act of war.

As tensions escalate, the international community watches closely, concerned about the implications for regional stability and human rights infringements in Venezuela.