AN ISLAND-WIDE blackout struck Cuba on Friday for the second time last week as the nation of nearly 10 million people grapples with fuel shortages stemming from a US energy blockade.

While total blackouts have become increasingly common in the Caribbean country, it’s unusual for back-to-back ones to hit just days apart.

Authorities in Cuba said the cause of the blackout was a “fluctuation in the parameters” following a failure in a line connecting the provinces of Santa Clara and Sancti Spiritus.

The electrical grid in Cuba is particularly fragile, due to the lack of maintenance of its ageing infrastructure, worsened by the US’s 66-year trade embargo on the country, and the scarcity of the fuels.

“It has been another very difficult week under the impact of the energy blockade: two disconnections of the National Electric System, almost no fuel to power the plants, and several units out of service,” Prime Minister Manuel Marrero said on his social media account.

Authorities reported that they have already begun restoring power to some areas.

Last Monday’s massive blackout was gradually being restored before Friday’s outage, the fourth so far this year.

A blackout in mid-May affected the island’s eastern provinces, while a blackout in mid-March struck the entire island.

Fuel has been running out across Cuba since January, when far-right US President Donald Trump threatened tariffs on any country that sells or provides oil to the island, deepening the island’s ongoing economic and financial crisis.

Public transport has largely been halted, and tens of thousands of surgeries have been cancelled.

Cuba produces only 40 per cent of the fuel it needs, while the 730,000 barrels of oil delivered by a Russian tanker in late March ran out by the end of April.

The government also has been rationing power with intentional outages that can stretch for more than 24 hours.