“This sanction being imposed on countries that sell oil to Cuba is very unfair… sanctions that harm the people are not right,” Sheinbaum told reporters.

Her country has been mulling how to send oil to Cuba without being punished by US President Donald Trump, who has promised to slap tariffs on any country that ships petroleum to Cuba.

Cuba, which is in the grips of an economic crisis, can no longer rely on oil supplies from Venezuela, whose leader was ousted in a deadly US military operation last month.

After Nicolas Maduro’s toppling, Trump claimed control of Venezuelan oil, vowed to starve Cuba of the commodity, and threatened tariffs on any other nation stepping in to help US-sanctioned Havana.

Sheinbaum has warned of a humanitarian crisis in Cuba, but is also keen to avoid putting her own country at risk of tariffs from Mexico’s main trading partner.

Mexico is seeking an agreement with Washington that would allow it to resume oil exports to Havana.

“We will continue supporting them and taking all necessary diplomatic actions to restore oil shipments,” Sheinbaum said Monday. “You cannot strangle a people like this — it’s very unfair, very unfair.”

In the meantime, Mexico said Sunday it had sent two ships with humanitarian aid to Cuba, which has had to suspend jet fuel supplies for a month because of an energy crisis triggered by the US attack on Venezuela.