Venezuela's government has imposed a two-day working week for public sector workers as a temporary measure to help it overcome a serious energy crisis.
Venezuela is facing a major drought, which has dramatically reduced water levels at its main hydroelectric dam.
But the opposition has accused the government of mismanaging the crisis.
The measures announced on national television by Mr Isturiz affect two million public sector workers.
President Nicolas Maduro had already given most of Venezuela's 2.8 million state employees Fridays off during April and May, to cut down on electricity consumption.
He said Venezuela had been badly hit by the El Nino weather phenomenon and would return to normal when it started raining again.
