Cuba blames the mounting crisis on a Cold War-era U.S. trade embargo and fresh restrictions from U.S. President Donald Trump, who recently tightened sanctions on the communist-run government and vowed to restore a "tough" policy toward the long-time U.S. foe.

Cuba's capital Havana plunged into darkness for a second night on Saturday as efforts to restore power proceeded in fits and starts, with setbacks slowing progress and leaving several million still without electricity across the island.

Cuba’s power grid collapsed Friday night, triggering a nationwide power outage and plunging its more than 10 million people into darkness. “At around 8:15 p.m. tonight, a failure at the Diezmero substation caused a significant loss of generation in the west of #Cuba and with it the failure of the National Electric System,