Three more ships with grain left Ukrainian ports on Friday headed to Turkey for inspection.
The ships are loaded with more than 58,000 tonnes of corn.
Experts say much of the grain that Ukraine exports is used as animal feed.
The three ships are from among more than a dozen bulk carriers and cargo ships that had been loaded with grain and stuck at Ukrainian ports since Russia invaded February 24.
Ukraine is one of the world's main breadbaskets, and the stocks of grain trapped were exacerbating a sharp rise of food prices and raising fears of a global hunger crisis.