Cuba made fast progress restoring power to swaths of the Caribbean island nation on Tuesday, both in Havana and outlying provinces, even as emergency and grid workers struggled to reach areas ravaged by Tropical Storm Oscar.

Cuba's power-grid operator said it had restored electricity to parts of Havana on Monday following multiple grid collapses over the past four days, while Tropical Storm Oscar lashed the island's eastern end.

Electricity has been restored to half of Havana, the Cuban capital's power company reported Monday, four days after the start of a nationwide blackout that the authorities have struggled to address. The government has said that electricity is expected to be restored to most of the country by the end of Monday.