MIAMI — The United States imposed new sanctions Thursday on Venezuela and Cuba and promised additional penalties against Nicaragua as the Trump administration laid out a hard-line policy toward countries the White House branded a “troika of tyranny.”

National security adviser John Bolton condemned what he called the “destructive forces of oppression, socialism and totalitarianism” that he said the three countries represent.

In a speech in Miami, home to thousands of exiles from Cuba, Venezuela and Nicaragua, Bolton said the U.S. “will no longer appease dictators and despots near our shores in this hemisphere.” He spoke at the Freedom Tower, an important landmark to the Cuban community in South Florida.

The administration will prohibit U.S. citizens from involvement in the gold export trade from Venezuela. American officials have said Venezuelan President Nicolas Maduro illegally exported at least 21 metric tons of gold to Turkey to avoid U.S. sanctions and to try to help rescue a collapsing economy once bolstered by vast oil reserves.

The U.S. government has sanctioned dozens of top Venezuelan officials as part of economic measures designed to pressure the South American country’s return to democracy.

Bolton blamed Cuba for enabling Maduro’s government and he urged the nations of the region to “let the Cuban regime know that it will be held responsible for continued oppression in Venezuela.”

In contrast to the Cuban policy of the Obama administration, Bolton said the State Department added more than two dozen entities owned or controlled by the Cuban military and intelligence services to a restricted list of entities with which financial transactions by U.S. persons are prohibited.

Bolton said the goal is to prevent dollars from reaching the Cuban military, security and intelligence services.

South Florida has long been home to a large community of Cubans emigres, many of whom will welcome a tougher line on the Havana government. In recent years, tens of thousands of Venezuelans have settled in the area as Venezuela’s economy has collapsed. Bolton’s speech may energize voters in both groups heading into Tuesday’s elections.

Bolton also sent a strong warning to President Daniel Ortega of Nicaragua, where more than 300 people have been killed since protests erupted in April calling for Ortega’s resignation.

“Free, fair, and early elections must be held in Nicaragua, and democracy must be restored to the Nicaraguan people,” he said. “Until then, the Nicaraguan regime, like Venezuela and Cuba, will feel the full weight of America’s robust sanctions regime.”

In grouping the three countries together, Bolton said “this troika of tyranny, this triangle of terror stretching from Havana to Caracas to Managua, is the cause of immense human suffering, the impetus of enormous regional instability, and the genesis of a sordid cradle of communism in the Western Hemisphere.”

Bolton mocked the leaders: “These tyrants fancy themselves strongmen and revolutionaries, icons and luminaries,” he said. “In reality, they are clownish, pitiful figures more akin to Larry, Curly, and Moe.”

On the other hand, Bolton called Brazil’s president-elect, Jair Bolsonaro, a “likeminded leader” and said his recent election victory demonstrates “a growing regional commitment to free-market principles and open, transparent, and accountable governance.”

Bolsonaro built his popularity on a mixture of often outrageous comments and hard-line positions, but he consolidated his lead by promising to enact market-friendly reforms.