Cuba's national electricity grid collapsed late on Sunday, the state-owned national electric utility said, plunging the island of about 10 million people into darkness as blackouts are becoming ever more frequent.
The Union Electrica de Cuba did not provide any further details in its posts on social media websites X and Facebook.
The outage follows three nationwide blackouts in July and comes as a US-imposed oil blockade has crippled the island's already aging energy infrastructure.
Cuba's national power grid last collapsed on 14 July, marking the third major blackout in nine days on the island.
"There has been a total disconnection of the electrical system," the energy ministry had said on social media.
The frequent outages come as a US-imposed oil blockade has crippled the island's already aging energy infrastructure.
US president Donald Trump imposed an oil blockade on the Caribbean island after Washington deposed Venezuelan president Nicolas Maduro on 3 January.
Venezuela was Cuba's primary fuel supplier, and subsequent US pressure also led Mexico to halt oil shipments to the island.
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