Some U.S. lawmakers are urging sanctions on Venezuelan officials, or even wider measures against the economy, but President Barack Obama's government has said that may harm prospects for political reconciliation here.
Anti-government demonstrations since February have led to violence in which 42 people have died.
About 800 people have also been injured and some 3,000 arrested, including more than 400 remaining behind bars, in what Maduro has cast as the suppression of a coup attempt but opponents say is a wave of repression.
"Now they're going round with this stupid idea that they're going to sanction us," Maduro said late on Friday, using the word "estupidos" which has a stronger connotation in Spanish.
"It's hardly worth responding to the stupid things the imperialist elites in the north do. They can keep their threats and stupidities," the 51-year-old successor to late socialist leader Hugo Chavez added in a speech to ecologists.
Last week's breakup of four student protest camps in Caracas, with the arrest of 243 youths, has revived tensions across Venezuela just as the movement appeared to be losing steam. Students and supporters were marching on Saturday.
"The protest must not and is not going to stop until there is liberty, democracy and sovereignty in Venezuela," said Miguel Barreto, a manager, manning a protest barricade in Caracas.