The United Nations expects the first grain cargo ships to leave Ukraine's Black Sea ports as soon as Friday.
Details about their route are still being worked out, it said.
UN Emergency Relief Coordinator Martin Griffiths said on Thursday in New York that there were freighters loaded with grain ready to go.
He said the exact coordinates for passage were still being finalized by Ukraine and Russia, plus the United Nations and Turkey.
The four parties reached a breakthrough last Friday to resume exports of Ukrainian grain through the Black Sea, raising hopes that food crises around the world could be alleviated.
Ukraine pledged to guide the ships through waters that have been mined and Russia promised to not target the ships and certain port infrastructure.
The United Nations and Turkey will help coordinate the exports and monitor the shipments in order to make sure the vessels are not smuggling weapons into the war zone.
Once the ships are moving and the deal fully implemented, Griffiths said exports from the ports should eventually reach pre-war levels of about 5 million tons per month.
More than 20 million tons of grain from last year's harvest are still awaiting export, according data from Ukraine, the country called the "Breadbasket of Europe."
