Cuba's power grid has collapsed for the third time this month, leaving the country in darkness with no electricity.
The cut came as the communist government continued to battle with a US imposed oil blockade and decaying infrastructure.
The Cuban Electric Union, which reports to the Ministry of Energy and Mines, announced on Saturday a total blackout across the island without initially giving a cause for the outage.
It later said that the blackout was caused by an unexpected failure of a generating unit at the Nuevitas thermoelectric plant in Camaguey province.
Grid operator and state utility Union Electrica said that the power failed at 6.32pm (10.32pm in the UK).
At 7am on Sunday (11am UK time), it said on social media that microsystems - smaller, closed circuits for vital services - were operational in all territories.
Work is underway to restore the rest of the grid. It's the second such blackout in a week on the island, and the third this month.
Sky's US partner network NBC News reports that both regional and national power outages have been common in Cuba over the past two years, due to breakdowns in ageing infrastructure.
However, the government has also blamed the strict oil and fuel embargo brought in by the Trump administration in February.
Cuba produces barely 40% of the fuel it needs to power its economy. The country's president, Miguel Diaz-Canel, said last week that the island had not received oil from foreign suppliers for three months.
Venezuelan President Nicolas Maduro and his wife were captured by the US military in early January, which led to the halt of Cuba's critical petroleum shipments from South America.
The US has also maintained a strict trade embargo on Cuba since 1962, the year after a failed, CIA-sponsored invasion of the island at the Bay of Pigs.
Donald Trump extended that blockade by signing an executive order imposing trade tariffs on countries exporting oil to Havana last month.
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The UN Office of the High Commissioner for Human Rights said experts condemned the move, and accused the US of a "serious violation of international law and a grave threat to a democratic and equitable international order".
On 15 March, Mr Trump claimed the US could "do whatever we have to do" in Cuba after his Iran war. His warning came a day after a rare riot against the Cuban government.
Videos on social media showed people throwing rocks through the windows of a building as they shouted "liberty" in the background.
(c) Sky News 2026: Cuba left in darkness after third power cuts in a month
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