By Simon Lewis and Dave Sherwood WASHINGTON/HAVANA, Jan 15 - The U.S. State Department's top aid official on Thursday said Cuba's authorities must not interfere with a shipment of humanitarian aid to its people and suggested President Donald Trump could take action if Cuba does not comply.

HAVANA — Tens of thousands of Cubans demonstrated Friday outside the U.S. Embassy in Havana to decry the killing of 32 Cuban officers in Venezuela and demand that the U.S. government release former Venezuelan President Nicolás Maduro.

For now, the Trump administration appears comfortable continuing to bleed Cuba economically without forcing its collapse. U.S. Energy Secretary Chris Wright told CBS News this week that the United States would allow Mexico, another of Cuba’s key oil suppliers, to continue selling fuel to the island.

President Trump stopped Venezuelan oil shipments to Cuba, and experts say disaster looms. Oil fuels its electric grid and without alternative supplies the country will plunge into extended darkness.

Only U.S.-bound tankers of crude have left the oil-exporting country since the arrest of Nicolás Maduro, a new report says.

Following the capture of Venezuelan strongman and Cuban ally Nicolas Maduro, President Donald Trump said Sunday Cuba won’t be receiving any more oil from the South American country and warned the government in Havana to “make a deal,

The Soviet Union was Cuba’s benefactor for decades. Venezuela took up the slack, and Mexico has supplied “humanitarian aid.” But the world is changing rapidly, our columnist says.

President Donald Trump warned Cuba there will be no more oil coming its way and told it to strike a deal, inciting a response from its leaders.

Though Mr Trump’s intentions are murky, it is obvious that Cuba’s regime is now unusually vulnerable. It has survived for decades by courting powerful backers like the Soviet Union to prop up its state-controlled economy.

Mexico, which was providing some oil to Cuba before Maduro's capture by the U.S., has become an especially key fuel supplier to the island since the Venezuelan leader's arrest, which was accompanied by the U.S. interception of vessels carrying oil to Cuba. Sheinbaum has referred to oil as "humanitarian aid."

President Donald Trump said in a post on Truth Social that Cuba would no longer receive oil or money from Venezuela.