Kluge, in Berlin, doesn’t believe that the Kremlin would accept such an arrangement. “Putin thinks he is winning the war,” Kluge said. “He has all the leverage.” A ceasefire would blunt his momentum and allow Ukraine to shore up its defenses. “And once you stop a war it becomes hard to start it again.”

President Donald Trump refused to label his Russian counterpart Vladimir Putin a dictator on Monday, despite having called the Ukrainian leader one in a post on his social-media platform, Truth Social,