CARACAS, Venezuela — President Nicolas Maduro claimed a popular mandate Monday to dramatically recast Venezuela’s political system, dismissing U.S. sanctions imposed on him and condemnations by his domestic opponents and governments around the world.

Washington added Maduro to a steadily growing list of high-ranking Venezuelan officials targeted by financial sanctions, escalating a tactic that has so far failed to alter his socialist government’s behavior. For the moment, the Trump administration did not deliver on threats to sanction Venezuela’s oil industry, which could undermine Maduro’s government but raise U.S. gas prices and deepen the humanitarian crisis here.

The sanctions came after electoral authorities said more than 8 million people voted Sunday to create a constitutional assembly endowing Maduro’s ruling party with virtually unlimited powers — a turnout doubted by independent analysts while the election was labeled illegitimate by leaders across the Americans and Europe.

Maduro said Monday evening he had no intention of deviating from plans to rewrite the constitution and go after a string of enemies, from independent Venezuelan news channels to gunmen he claimed were sent by neighboring Colombia to disrupt the vote as part of an international conspiracy led by the man he calls “Emperor Donald Trump.”

Venezuela’s National Electoral Council said turnout in Sunday’s vote was 41.53 percent, or 8,089,320 people. Opposition leaders estimated the real turnout at less than half the government’s claim in a vote watched by government-allied observers but no internationally recognized poll monitors.

Opinion polls had said some 85 percent of Venezuelans disapproved of the constitutional assembly and similar numbers disapproved of Maduro’s overall performance.