Bulent Kilic | AFP | Getty Images Ukraine’s president said on Sunday that the country’s harvest could be half the usual amount this year because of Russia’s invasion of Ukraine. “Ukraine’s harvest this year threatens to double,” President Volodymyr Zelenskiy tweeted in English, suggesting half the usual amount. “Our main goal is to prevent the global food crisis caused by the Russian invasion. Grains find a way to be delivered alternatively,” he added. Ukraine, a key global grain supplier, has struggled to get its product to buyers because of Russia’s naval blockade of Ukraine’s Black Sea ports. An agreement brokered by the UN and Turkey on July 22 provides for the safe passage of ships carrying grain from three ports in southern Ukraine. Speaking at one of those ports on Friday, Ukraine’s infrastructure minister said Ukraine was ready to start shipping grain and that he hoped the first ships would leave by the end of the week.