Normally, almost all of Ukraine's grain exports go by sea. Today, Russia has occupied some of Ukraine's ports and destroyed infrastructure at others.
Even those that remain intact and under government control are unusable, because of mines and Russian warships. The shortfall in grain deliveries from Ukraine has sent food prices skyrocketing and led to fears of famine, especially in Africa, where some countries get more than 90 percent of their wheat from either Ukraine or Russia.
Western leaders, including French President Emmanuel Macron,have vowed to find a solution. But many doubt whether Russia would stick to any deal.
In the meantime, exporters have been scrambling to find alternative ways to get at least some of the produce out of the country, leading to huge queues at the borders, as well as on the Danube River.