Mr. Zelensky wrote on X that his discussions with Prince Mohammed, the de facto Saudi leader, who has sought to take a central role on the world’s diplomatic stage, were “good” and that he was “grateful” for the crown prince’s “wise perspective on global affairs and support for Ukraine.” Mr. Zelensky added that it was “especially important to hear words of confidence in Ukraine’s future.”

Their meeting came ahead of talks planned for Tuesday between Ukrainian and U.S. officials in the oil-rich Gulf state.