The U.S. on Wednesday imposed sanctions on Venezuela, Nicaragua and Cuba, with national security adviser John Bolton dubbing the leaders of those countries the "three stooges of socialism” during a speech in Miami.

In his speech on the anniversary of the Bay of Pigs operation, Bolton said the leadership of the three countries are starting to lose power. “The United States looks forward to watching each corner of this sordid triangle of terror fall: in Havana, in Caracas, and in Managua,” Bolton said, referring to the countries as a “troika of tyranny."

The latest Venezuela sanctions blacklist Banco Central de Venezuela, as well as one of its directors, Iliana Josefa Ruzza Terán. Treasury Secretary Steven Mnuchin said that the move against the central bank was taken to prevent the institution from “being used as a tool” by Nicolas Maduro.

Maduro’s inner circle “continues to plunder Venezuelan assets and exploit government institutions to enrich corrupt insiders,” Mnuchin said.

The Treasury issued some licenses alongside its sanctions on Banco Central de Venezuela, which authorize certain transactions for humanitarian aid or remittances. “While this designation will inhibit most Central Bank activities undertaken by the illegitimate Maduro regime, the United States has taken steps to ensure that regular debit and credit card transactions can proceed and personal remittances and humanitarian assistance continue unabated and are able to reach those suffering under the Maduro regime’s repression,” Mnuchin said.

Ruzza Terán, a director of the central bank, was appointed in May 2018 as vice president of finance at the state-owned oil firm Petróleos de Venezuela SA (PdvSA), the Treasury said. She also was appointed in July 2018 as a director on the board for the Venezuelan Department of Foreign Commerce, according to the Treasury.