Russian President Vladimir Putin and his Turkish counterpart, Recep Tayyip Erdogan, are holding talks on whether to revive an agreement that allows Ukraine to ship its grain through the Black Sea.
The leaders met in the southern Russian resort of Sochi on Monday.
Ukraine is a major grain exporter. The country's exports had been cut off since Russia's invasion, but Turkey and the United Nations brokered the deal to resume the exports last summer.
In July of this year, Russia pulled out of the agreement, raising concerns about a possible global food crisis.
Last Thursday, UN Secretary-General Antonio Guterres told reporters that he had presented Russia with a set of new proposals in a bid to bring Moscow back to the agreement. Turkey expressed hopes for the revival of the deal. But the details of the proposals have not been disclosed.
Russian Foreign Minister Sergey Lavrov stressed that smooth exports of farm products from Russia must be ensured.
Ahead of Monday's meeting of the two leaders, the Russian military carried out drone attacks for two consecutive nights in the southern Ukrainian region of Odesa, where grain shipping infrastructure is located.
As Russia maintains a hardline stance against Ukraine, attention is focused on whether Erdogan can convince Putin to return to the deal.