US Secretary of State Marco Rubio has been holding talks with the grandson of Cuba's former leader Raul Castro, according to US media reports.
The talks between Rubio, 54, and Raul Guillermo Rodriguez Castro, 41, are bypassing official Cuban government channels.
"I wouldn't call these 'negotiations' as much as 'discussions' about the future," a senior Trump administration official said, referring to the talks between Rubio and Raul Guillermo Rodriguez Castro, the Axios news site reported on Wednesday.
US President Donald Trump said on Monday that the US is talking to Cuba "right now" and Rubio is holding the talks.
"Cuba is right now a failed nation, and they don't even have jet fuel to get for airplanes to take off…We're talking to Cuba right now...and they should absolutely make a deal," Trump told reporters.
The senior official said the US government's position "is the regime has to go."
"But what exactly that looks like is up to (President Trump) and he has yet to decide. Rubio is still in talks with the grandson," the official was quoted as saying by the news site.
Rubio has not held talks with Cuba’s official leader, President Miguel Diaz-Canel Bermudez, or with any other senior government officials.
The US has reinstated its blockade of Cuba, declaring its intention to overthrow the republic's communist government by one means or another.
Washington has imposed an embargo on fuel deliveries to the island nation, which was already facing acute shortages.
The US previously succeeded in halting oil supplies to Cuba from Mexico and Venezuela, and in the latter case, US forces abducted President Nicolas Maduro.
Washington has also announced its intention to impose proportional import duties on goods from countries that dare to supply fuel to Cuba.
