U.S. President Donald Trump on Thursday threatened new tariffs on countries supplying oil to Cuba, escalating a pressure campaign against the island.

The move, authorized by an executive order under a national emergency declaration, did not specify any tariff rates or single out any countries whose products could face U.S. tariffs.

Trump said this week that "Cuba will be failing pretty soon," adding that Venezuela, once the island's top oil supplier, has not recently sent oil or money to Cuba.

Havana depended on Venezuela for more than one third of its oil needs, according to energy industry analysts.

Trump has used tariff threats as a foreign policy tool throughout his second term in office.

Cuba's president said this month Washington had no moral authority to force a deal on Cuba after Trump suggested the island should strike an agreement with the United States.