The presidents of Russia and Turkey are meeting on Monday, with Turkish leader Recep Tayyip Erdogan seeking to persuade Russia to revive an agreement that allowed Ukraine to export grain and other commodities from three Black Sea ports despite the war. Russian President Vladimir Putin in July refused to extend the agreement, which was brokered by Turkey and the United Nations a year earlier. Russia complained that a parallel deal promising to remove obstacles to Russian exports of food and fertilizer hadn’t been honored. The leaders are to meet in the Black Sea city of Sochi, where the Russian president has a residence.