“Russia has to get out. What’s your next question?” Mr. Trump told reporters.

In recent weeks, Russia has offered to send food and medicine to the Maduro government as the country deals with hyperinflation, widespread blackouts and skyrocketing poverty. American-led aid shipments, staged in nearby countries including Colombia and Brazil, have had less success making it across the country’s borders.

“They know,” Mr. Trump said when asked if he had conveyed to the Russians his feelings about their involvement in Venezuela. “They know very well.”