Venezuela has accused US President Donald Trump of making a "colonialist threat" after he said the airspace around the country should be considered closed.

The country's foreign ministry called Trump's comments "another extravagant, illegal and unjustified aggression against the Venezuelan people".

The US does not legally have the authority to close another country's airspace, but Trump's online post could lead to travel uncertainty and deter airlines from operating there.

The US has been building its military presence in the Caribbean, which officials say is to combat drug smuggling. Venezuela's President Nicolás Maduro has dismissed US claims of drug trafficking as an attempt to oust him.

In a post on Truth Social, Trump wrote: "To all Airlines, Pilots, Drug Dealers, and Human Traffickers, please consider THE AIRSPACE ABOVE AND SURROUNDING VENEZUELA TO BE CLOSED IN ITS ENTIRETY."

The White House did not immediately respond to the BBC's request for comment.

With Trump ratcheting up his threats, Democrat and Republican members of US Congress have expressed anger that he has not sought legislative approval.

"President Trump's reckless actions towards Venezuela are pushing America closer and closer to another costly foreign war," top Senate Democrat Chuck Schumer posted on X on Sunday.

"Under our Constitution, Congress has the sole power to declare war," he added.

Republican Representative Marjorie Taylor Greene, until recently a close Trump ally, said: "Reminder, Congress has the sole power to declare war."

Trump's comments come days after the US Federal Aviation Administration (FAA) warned airlines of "heightened military activity in and around Venezuela".

In a statement on Saturday, Venezuela's foreign ministry said that the US had "unilaterally suspended" its weekly migrant repatriation flights.

"We call directly on the international community, the sovereign governments of the world, the UN, and the relevant multilateral organizations to firmly reject this immoral act of aggression," it said.

Also Saturday, Venezuela's military conducted exercises along coastal areas, with state TV showing anti-aircraft weapons and other artillery being manoeuvred.

Venezuela on Wednesday banned six major international airlines – Iberia, TAP Portugal, Gol, Latam, Avianca and Turkish Airlines – from landing there after they failed to meet a 48-hour deadline to resume flights.

The US has deployed the world's largest aircraft carrier, the USS Gerald Ford, and about 15,000 troops to within striking distance of Venezuela.

It has insisted that the deployment – the largest by the US in the region since it invaded Panama in 1989 – is to combat drug trafficking.

On Thursday, Trump warned that US efforts to halt Venezuelan drug trafficking "by land" would begin "very soon".

US forces have carried out at least 21 strikes on boats they said were carrying drugs, killing more than 80 people. However, the US has not provided evidence that the boats carried drugs.

The Venezuelan government believes the aim of the US action is to depose Maduro, whose re-election last year was denounced by the Venezuelan opposition and many foreign nations as rigged.

The US has also designated Cartel de los Soles, or Cartel of the Suns – a group it alleges is headed by Maduro – as a foreign terrorist organisation.

Labelling an organisation as a terrorist group gives US law enforcement and military agencies broader powers to target and dismantle it.

Venezuela's foreign ministry has "categorically, firmly, and absolutely rejected" the designation.

Venezuela's interior and justice minister Diosdado Cabello, who is alleged to be one of the high-ranking members of the cartel, has long called it an "invention".

The US state department has insisted that the Cartel de los Soles not only exists, but that it has "corrupted Venezuela's military, intelligence, legislature, and judiciary".