Ukraine says 12 ships loaded with grain left its Black Sea ports on Monday, despite Russia's withdrawal from a key deal facilitating exports.
A senior Ukraine official said one of the vessels with 40,000 tons of grain was for Ethiopia "who faced the real possibility of mass starvation".
Moscow pulled out from the deal after a drone attack on its Black Sea Fleet in the annexed Crimea peninsula.
The Kremlin blamed Kyiv for Saturday's attack, saying "the Russian side cannot guarantee the safety of civilian dry cargo ships".
Kyiv has not admitted responsibility for the attack, saying Moscow had long planned to abandoned the internationally-brokered deal and used the attack as a pretext to do so.
After Russia invaded Ukraine in February, its navy imposed a blockade on Ukraine's Black Sea ports, trapping about 20 million tonnes of grain meant for export inside the country, along with other foodstuffs such as maize and sunflower oil.