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 Guzmán 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 re­spect both of our in­ter­nal af­fairs.”