HAVANA — Cuba’s national electric grid collapsed on Monday, the country’s grid operator said, leaving around 10 million people without power amid a U.S.-imposed oil blockade that has crippled the island’s already obsolete generation system.

Cuba’s grid operator ​UNE said on social ⁠media it was investigating the causes of the ‌blackout, the latest ‌in a series of widespread outages that stem ⁠from hours or days ⁠and that this weekend sparked a rare violent protest in the Communist-run country.

The United States has tightened the screws this year on long-time foe Cuba since capturing Venezuelan President Nicolas Maduro — ‌Cuba’s most important foreign benefactor — in ​early January.

President Donald Trump cut off Venezuelan oil shipments to Cuba and threatened to slap tariffs on any country that sells oil to Cuba, strangling the island’s already antiquated grid.

Cuba said on Friday that it had entered into ​talks with the U.S. with the hope of defusing ‌the crisis.

Trump has ‌said ⁠repeatedly in recent weeks that Cuba is on the verge of collapse and was eager to make a deal with the United States.

Cuban President Miguel ‌Diaz-Canel said last week ​that the island had ‌not received a ⁠shipment of ​fuel in three months.