Government offices in Iran are closed or operating at reduced hours. Schools and colleges have moved to online only. Highways and shopping malls have descended into darkness, and industrial plants have been denied power, bringing manufacturing to a near halt.

Although Iran has one of the biggest supplies of natural gas and crude oil in the world, it is in a full-blown energy crisis that can be attributed to years of sanctions, mismanagement, aging infrastructure, wasteful consumption — and targeted attacks by Israel.

“We are facing very dire imbalances in gas, electricity, energy, water, money and environment,” said President Masoud Pezeshkian in a live televised address to the nation this month. “All of them are at a level that could turn into a crisis.”

While Iran has been struggling with issues with its infrastructure for years, the president warned that the problem had reached a critical point.

For most of last week, the country was virtually shut down to save energy. As ordinary Iranians fumed and industrial leaders warned that the accompanying losses amounted to tens of billions of dollars, Mr. Pezeshkian could offer no solution other than to say he was sorry.

“We must apologize to the people that we are in a situation where they have to bear the brunt,” Mr. Pezeshkian said. “God willing, next year we will try for this not to happen.”