New Delhi, April 24 -- Havana will not abide by any American "ultimatums" to release political prisoners as part of new talks, a Cuban diplomat said Thursday, while asserting that leaders are "preparing for all scenarios" if U.S. President Donald Trump makes good on threats to intervene in the island nation.

In an interview with The Associated Press, Cuban Ambassador to the U.N. Ernesto Soberón Guzman said internal issues regarding detainees "are not on the negotiating table." The release of political prisoners was a key U.S. demand as the longtime adversaries held discussions in Cuba this month for the first time in a decade.

"We have our legal system, like here in the U.S., they have their legal system," he said. "So we have to r...