Cuba has been suffering severe economic tumult led by an energy shortage that plunged 65% of the country into darkness on Tuesday.
Cuba’s leaders have blamed US sanctions but Rubio, a Cuban-American and vociferous critic of the government established by Fidel Castro, said the system was to blame including corruption by the military.
“It’s a broken, nonfunctional economy, and it’s impossible to change it. I wish it were different,” he told Fox News host Sean Hannity on Air Force One as he traveled with President Donald Trump to China.
“We’ll give them a chance. But I don’t think it’s going to happen,” Rubio said.
“I don’t think we’re going to be able to change the trajectory of Cuba as long as these people are in charge in that regime.”
Trump — who since the start of the year has deposed Venezuela’s leftist leader but seen less success in a war on Iran — has mused that Cuba could be next and that the US could take over the island 145 kilometers (90 miles) off Florida.
Rubio said last week after talks at the Vatican that Cuba had rejected a US offer for US$100 million in assistance, an assertion denied by Havana.
The State Department publicly renewed the proposal on Wednesday, a week after new US sanctions targeted key actors in Cuba’s state-controlled economy and their foreign partners.
“The regime refuses to allow the US to provide this assistance to the Cuban people, who are in desperate need of assistance due to the failures of Cuba’s corrupt regime,” the State Department said in a statement.
“The decision rests with the Cuban regime to accept our offer of assistance or deny critical (life)-saving aid and ultimately be accountable to the Cuban people for standing in the way of critical assistance,” it said.
It said the support would include direct humanitarian assistance and funding for “fast and free” internet access — which presumably would benefit dissidents in the one-party state that restricts media.
Cuba has seen a series of rare protests as economic misery grips the island of 9.6 million people.
On Wednesday, several dozen people, some banging pots and pans, protested against power outages in the San Miguel del Padron neighborhood on Havana’s outskirts, a resident told AFP.
Several other neighbourhoods saw similar protests by evening, with residents in Playa shouting, “Turn on the lights!”, witnesses told AFP.
Cuban President Miguel Diaz-Canel acknowledged the “particularly tense” situation but pinned blame squarely on the US.
“This dramatic worsening has a single cause: the genocidal energy blockade to which the US subjects our country, threatening irrational tariffs against any nation that supplies us with fuel,” he wrote Wednesday on X.
Cuba lost the source for around half its fuel needs when US forces snatched Venezuelan leader Nicolas Maduro in a stunning raid in January, with his successor complying with US pressure not to aid Cuba.
Since then, only one oil tanker, from Russia, has reached Cuba.
The Trump administration already provided US$6 million in humanitarian aid to Cuba but channeled it through the charity of the Catholic Church, which has long played a go-between role for the two countries.
After Rubio’s initial comments on the US$100 million offer, Foreign Minister Bruno Rodriguez said it was a “lie” that “no one here knows anything about.”
“Will it be a donation, a deception or a dirty deal to curtail our independence? Wouldn’t it be easier to lift the fuel blockade?” Rodriguez wrote on X.
Rubio has been widely reported to be in contact with segments of the Cuban elite in hopes of stirring change.