Venezuela has accused Donald Trump of a "colonial threat" after he said the airspace "above and surrounding" the country should be considered closed "in its entirety".
Mr Trump made the declaration amid growing tensions with President Maduro - and as the US continues attacking boats it claims are carrying drugs from Venezuela.
He wrote on Truth Social: "To all Airlines, Pilots, Drug Dealers, and Human Traffickers, please consider THE AIRSPACE ABOVE AND SURROUNDING VENEZUELA TO BE CLOSED IN ITS ENTIRETY."
Venezuela's foreign affairs office called it a "colonial threat" and "illegal, and unjustified aggression".
It accused the president of threatening "the sovereignty of the national airspace... and the full sovereignty of the Venezuelan state".
President Trump's words were part of a "permanent policy of aggression against our country" that breached international law and the UN Charter, it added.
The Pentagon and the White House have so far not given any additional detail on the president's statement.
Mr Trump's post comes after the American aviation regulator last week warned of a "potentially hazardous situation" over Venezuela due to a "worsening security situation".
The South American nation revoked operating rights for six major airlines that went on to suspend flights to the country.
Mr Trump warned a few days ago that land operations against suspected Venezuelan drug traffickers would begin "very soon".
Such a move would be a major escalation in Operation Southern Spear - the US naval deployment in the Caribbean Sea and eastern Pacific that's so far attacked at least 21 vessels.
Venezuela has said the attacks, which have killed more than 80 people, amount to murder.
The US has released videos of boats being targeted, but hasn't provided evidence - such as photos of their cargo - to support the smuggling claims.
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The Pentagon has sought to justify the strikes by labelling the drug gangs as "foreign terrorist organisations" - putting them on par with the likes of al Qaeda.
It claims the boats targeted are carrying drugs bound for the US, although Sky's chief correspondent says the final destination is likely to be Europe and West Africa.
President Maduro has denied Mr Trump's claims he is involved in the drugs trade himself and said his counterpart wants to oust him so he can install a more sympathetic government.
Venezuelan officials have also claimed Mr Trump's true motivation is access to the country's plentiful oil reserves.
Mr Maduro is widely considered a dictator who's cheated elections and has been president since 2013.
(c) Sky News 2025: Venezuela accuses Trump of 'colonial threat' after US president 'closes' its airspace
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