The US has seized a sixth tanker in the Caribbean Sea in its ongoing efforts to control exports of Venezuelan oil, officials say.

The vessel, Veronica, was boarded in a predawn operation 'without incident' as it was defying President Donald Trump's 'quarantine of sanctioned vessels,' said the US military.

'The only oil leaving Venezuela will be oil that is coordinated properly and lawfully,' the Southern Command said.

Since the US military strikes on Venezuela and the seizure of its president Nicolás Maduro this month, Trump has indicated plans to tap into the country's vast oil reserves.

'The Veronica is the latest tanker operating in defiance of President Trump's established quarantine of sanctioned vessels in the Caribbean,' US Southern Command stated on social media.

The military shared a video showing Marines and sailors boarding the tanker.

Veronica, a crude oil tanker sailing under a Guyanese flag, departed empty from Venezuelan waters in early January, according to TankerTrackers.com. The International Maritime Organization's database indicates that the vessel was previously registered in Russia under different names.

Homeland Security Secretary Kristi Noem announced that the operation was carried out in close coordination with military, state, and justice department colleagues, highlighting the effectiveness of US Coast Guard operations.

This seizure underscores Washington's crackdown on the so-called dark fleet that comprises more than 1,000 vessels transporting sanctioned oil, as the US collaborates with Venezuela's interim government to regulate oil sales.

Moreover, this incident follows a recent announcement regarding the US's successful first sale of Venezuelan oil, valued at $500 million.

Trump has urged oil executives to invest $100 billion in Venezuela's energy infrastructure, although significant changes will be necessary to attract investment.

The latest tanker seizure coincided with a White House meeting between Trump and Venezuela's opposition leader Maria Corina Machado, whom Trump has previously called a 'freedom fighter' but hesitated to appoint as Venezuela's leader.