Scattered protests have broken out across Havana, with residents banging pots, honking horns and shouting "turn on the lights" as millions of Cubans remain without power amid a six-month-long US fuel blockade.
Cuba experienced a nationwide outage on Monday - its third this year - but while authorities said most of the country had been reconnected to the island's grid by late Tuesday, many remained in the dark and without electricity as the island doesn't have enough fuel.
The country's grid operator UNE said it had reconnected the grid from Pinar del Rio, in far western Cuba, to Holguin in the east. Santiago de Cuba, the island's second-largest city, remained disconnected and without power, authorities said.
The US in January cut off Cuba's fuel supply, then imposed fresh sanctions that have prompted an exodus of foreign businesses and a near-complete collapse of tourism in a bid to force the island's government to the negotiating table.
The US is seeking to upend Cuba's communist-run government and has called for democratic elections and the release of "political" prisoners.
Cuba and the United Nations say US President Donald Trump's sanctions are a violation of international law and the human rights of the island's residents.
Hundreds of exhausted residents in the outlying Havana neighbourhoods of Jaimanitas and Santa Fe took to the streets while others sat on doorsteps and sidewalks during the hot night, playing dominoes or chatting with neighbours while waiting for power to be restored.
Many, now accustomed to blackouts spanning 30 hours or more, had largely resigned themselves to another night of swatting mosquitoes and little sleep.
"I don't see a quick fix to this problem," said Amauri Gonzalez, a local resident who had stepped outside his home for a bit of fresh air.
"Our power plants are obsolete and there's no fuel."
In some areas of Santa Fe, the power returned shortly after the pot-banging began, sending protesters scurrying to their homes to take advantage.
Talks between the two nations have stagnated.
US Ambassador to the United Nations Michael Waltz told a Tuesday debate on US sanctions at the UN General Assembly that Cuba's government was to blame for the electricity shortfalls.
"Change your ways and turn the lights back on for your people," he said.
The vast majority of countries that spoke during the debate, however, called on Washington to end the blockade and reverse the sanctions that have crippled the island's economy.