The United States blacklisted Venezuela's Vice President Tareck El Aissami for drug trafficking, the first crackdown by the Trump administration against a top official in President Nicolas Maduro's government for money laundering and the drug trade.

The U.S. Department of Treasury said it designated El Aissami for sanctions under the Foreign Narcotics Kingpin Designation Act. His associate, Samark Jose Lopez Bello, was targeted for providing material assistance and financial support for El Aissami's activities, Treasury said in a statement.

Treasury also targeted 13 companies owned or controlled by Lopez Bello or other parties that comprise an international network spanning the British Virgin Islands, Panama, Britain, the United States and Venezuela.

"El Aissami facilitated shipments of narcotics from Venezuela, to include control over planes that leave from a Venezuelan airbase, as well as control of drug routes through the ports of Venezuela," a senior U.S. administration official told a conference call with reporters.

The Treasury Department said El Aissami oversaw or partially owned narcotics shipments of more than 1,000 kilograms from Venezuela on multiple occasions, including shipments to Mexico and the United States.

Another U.S. administration official estimated the value of property blocked in Miami was worth "tens of millions of dollars." Another official suggested the value of the property seized was not commensurate with the salary of a public official.

U.S. officials called Lopez Bello a "key frontman" used by El Aissami to handle financial matters and purchase assets.

The Venezuelan government did not immediately respond to a request for comment. Maduro frequently accuses U.S. officials of trying to smear his administration.

U.S. officials denied that Monday's designations had anything to do with El Aissami's prominent political role. He is a former minister of interior and of justice.

"The designation is a result of a years long investigation of narcotics trafficking by OFAC. The designation is not aimed at Venezuela or any specific sectors of the Venezuelan economy," the senior official said.

As a result of these actions, Americans are generally prohibited from engaging in transactions or otherwise dealing with individuals and entities, and any assets they have under U.S. jurisdiction are frozen.