HAVANA/MEXICO CITY -- Cuba on Monday denied holding any conversation with the US government beyond technical contacts on immigration matters, but reiterated the willingness to negotiate.

Cuban President Miguel Diaz-Canel said that his country has always been willing to engage in "serious and responsible" dialogue with various US administrations, including the current one.

He emphasized that such dialogue must be conducted "on the basis of sovereign equality, mutual respect, principles of international law, mutual benefit, without interference in internal affairs, and with full respect for our independence."

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Diaz-Canel noted that "Cuba scrupulously complies with" the existing bilateral immigration agreements, adding that "As history has shown, for US-Cuba relations to progress, they must be based on international law rather than on hostility, threats, and economic coercion."  

Mexico offers to mediate 

Mexico is willing to act as a mediator if the United States and Cuba agree to dialogue, President Claudia Sheinbaum said on Monday.

"If Mexico were to become a vehicle to facilitate communication between the United States and Cuba, both parties would agree," she said at a regular morning press conference following her phone conversation earlier in the day with US President Donald Trump.

"Mexico is in the best position to do so," she added, referring to acting as mediator.

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In a post on social media on Sunday, Trump said, "No more oil or money will be sent to Cuba," and recommended the Cuban government make a deal with Washington "before it's too late."

Sheinbaum said that shipping Mexican oil to Cuba is legal within the framework of national sovereignty and for humanitarian purposes.

The humanitarian aid is "not new," and this policy has been supported by successive Mexican administrations, regardless of their political affiliation, she said.