"The threats pose potential risks to flights at all altitudes, including overflights, takeoffs and landings, and to aircraft on the ground," the FAA wrote on Friday.
The warning comes at a time when the US has struck a number of ships suspected of smuggling drugs from Venezuela. But the US warnings also concern the Venezuelan regime and the country's authoritarian President Nicolás Maduro, who is accused of supporting drug trafficking.
Maduro has responded by putting the country's military on war alert.
The US has carried out more than 20 attacks on ships in the Caribbean Sea and the eastern Pacific Ocean since September. About 80 people have been killed in the attacks.
The United States has not yet presented evidence that the ships were smuggling drugs.
