The first ship carrying Ukrainian grain through the Black Sea since Russia invaded Ukraine more than five months ago left Odesa on Monday under a safe passage agreement that has raised hopes hundreds of other vessels will follow.
But there are many hurdles to overcome before millions of metric tons of Ukrainian grain depart from its Black Sea ports, which handle most of the corn, wheat, barley, sunflowerseed and rapeseed exports of one of the world's top grain suppliers. Here are some of the issues:
What about the sea mines?