HAVANA — Swaths of Cuba remained without power on Thursday nearly a day after a huge blackout hit the western part of the island in the latest outage blamed on a fragile electric grid and a lack of fuel.

Crews worked overnight to repair a broken boiler at one of Cuba’s largest thermoelectric plants, but officials have warned that it could take three to four days for power to be fully restored.

State media reported that nearly 660,000 customers in Havana, or 77%, had power, as well as 43 hospitals and 10 water supply stations. However, officials warned of low power generation and said some circuits that crews had reconnected were kicked offline again.

Millions still remained without power, including Miguel Leyva, 65, who lives with his mother and brother, both of whom are ill.

“I have no words to describe what I’m going through: the heat, the mosquitoes and no electricity. The food could spoil,” he said. “I’m aware of all the problems that exist, but listen, it’s been more than 24 hours now.”

Cuba’s Ministry of Energy and Mines wrote on X that the electrical system is operating “in a limited capacity, prioritizing basic services, primarily health and water supply.”

State media reported that two power plants are offline because of a lack of petroleum.

Government officials said Wednesday afternoon that crews have located the crack in the boiler drum that led to the outage. They said it will take 12 hours to cool that area so crews can enter the furnace and start repairing it. Work already is underway to fix a pipe that also is damaged, officials added.

Cuba has long struggled with an aging electric grid and intermittent fuel supplies, but the crisis has deepened in recent months.

Key oil shipments from Venezuela were halted after the United States attacked the South American country in early January. Then later that month, U.S. President Donald Trump warned that he would impose tariffs on any country that sells or supplies oil to Cuba.

On Thursday, Trump suggested a deal may be imminent with Cuba but that he’s focusing on Iran in the meantime.

Referring to a co-owner of Inter Miami being originally from Cuba, Trump said, “You’re gonna go back” and added, “That’s going to be a great day, right?”

Without providing details, Trump said, “We’re going to celebrate that separately. I just want to wait a couple of weeks. I want him to wait a couple of weeks. But we’ll be together again soon, I suspect, celebrating what’s going on in Cuba.”

He added of the island’s government, “They want to make a deal so badly. You have no idea.”

Then, referring to Marco Rubio, the president said the secretary of state wants to work on Cuba but is cautious to do so during the war in Iran.