The second shipment of humanitarian food aid since Russia's invasion left Ukraine for Yemen on Tuesday, the World Food Programme said in a statement.
The MV Karteria left from the Black Sea port of Yuzhny and will stop in Turkey along the way for the grains to be milled into flour, the UN agency said.
Ukraine's grain exports have slumped since the start of the war in February because of port closures, driving up global food prices and increasing hunger in some of the poorest parts of the world.
A deal brokered by Turkey and the United Nations in July helped unblock them, and so far more than 1 million tonnes of food has been exported through the Black Sea initiative.
(Reporting by Emma Farge, Editing by Miranda Murray)
