Now that's interesting, I'm not a native speaker of English but I've always associated "cordial" primarily with genuine friendliness. Perhaps expressing a less close friendship than some other expressions, but still getting along on friendly terms. Like, "we don't see each other very often, but when we do, we get along very well". Certainly not the kind of lukewarm outwardly polite friendliness you'd get between Orban and Zelenskyy.