"To all airlines, pilots, drug dealers and human traffickers, please consider the airspace over and around Venezuela to be completely closed," Trump writes, partly in capital letters.
The president does not elaborate further on what he means, but the statement comes against the backdrop of tensions between the United States and Venezuela.
The United States has carried out repeated military strikes against what it describes as drug-smuggling boats in recent months. More than 80 people have been killed in the American attacks.
Recently, Trump also said that the US plans to stop drug smugglers from Venezuela on land as well.
At the same time, several American warships, including an aircraft carrier, have been moved to the Caribbean Sea near Venezuela.
Trump spoke by phone this week with Venezuelan President Nicolás Maduro, whom the United States has identified as partly responsible for the smuggling. The leaders reportedly discussed a possible meeting, according to The New York Times.
