Secretary of State John Kerry said on Wednesday that President Nicolas Maduro of Venezuela had failed to negotiate in good faith with his political opponents and warned that the United States Congress was moving to legislate economic sanctions. "Regrettably, there has just been a total failure by the government of Venezuela to demonstrate good-faith actions," Mr. Kerry said during a visit there. "What is important is for the Venezuelan government now to honor the dialogue process and to restore the civil liberties of opposition leaders who have been unjustly imprisoned." Mr. Kerry, who is making his first trip to Mexico as secretary of state, met Wednesday with his Mexican counterpart, Jose Antonio Meade, and with Enrique Nieto, the Mexican president.