Venezuelan President Nicolas Maduro arrested two opposition leaders to send a message of defiance to President Trump, according to Sen. Marco Rubio.

President Trump's team froze Maduro's assets after the Venezuelan leader proceeded with a plan to rewrite the nation's constitution, part of Maduro's effort to disempower an opposition-controlled legislature. Those sanctions failed to deter the authoritarian from arresting two political dissidents, including Leopoldo Lopez, whose release from prison three weeks ago was celebrated by Vice President Mike Pence and the State Department.

"There should be no doubt that his arrest is a direct challenge to President Trump," Rubio, a Florida Republican who sits on the Foreign Relations Committee, said Tuesday.

Venezuela is going through a food crisis, sparking protests against the government. Maduro and his allies responded by seizing power from the national legislature, which is the only branch of government controlled by opposition leaders. The arrest of Lopez reverses a release made just last month, after he had served three years in prison.

"Maduro's regime has lost all legitimacy," Nikki Haley, U.S. Ambassador to the United Nations, tweeted Tuesday.

The arrest of Lopez and Antonio Ledezma isn't the only time Maduro has tangled with the Trump team. As the successor to the late Hugo Chavez, Maduro hasn't hesitated to repeat Chavez's tactic of a direct confrontation with U.S. leaders. He attacked Trump personally in May, following an earlier round of sanctions targeting Venezuelan officials. "Go home, Donald Trump. Get out of Venezuela," Maduro yelled in a televised speech. "Get your dirty hands out of here."

Rubio urged Trump to follow through with a threat to impose additional economic sanctions. "This is a promise I remain confident the president will keep," he said.