Expected negotiations between Russian President Vladimir Putin and Turkish President Tayyip Erdogan remain the only hope to extend the Black Sea grain deal that is set to expire next week, Russia's RIA news agency reported on Monday.

The Black Sea deal, brokered between Russia and Ukraine by the United Nations and Türkiye in July 2022, aimed to prevent a global food crisis by allowing Ukrainian grain to be safely exported from Black Sea ports amid Russia's military operation.

Citing an unnamed source familiar with negotiations, RIA reported that "there is no optimism" for the extension of the deal – a position that Moscow has reiterated frequently in recent weeks.

"Our practice shows that it is the negotiations between the two leaders that are able to change the situation, the current difficult period is no exception," RIA quoted the source as saying.

"Today, this remains the only hope."

Erdogan said on Saturday he was pressing Russia to extend the grain deal, currently due to expire on July 17, by at least three months and announced a visit by Putin in August.

The Kremlin said over the weekend that there was no phone call scheduled and that there was no certainty about the two leaders meeting.

Ankara angered Moscow with its July 8 decision to release to Kyiv five detained Ukrainian commanders of a unit that for weeks defended a steel works in the Ukrainian city of Mariupol, with the Kremlin saying Ankara violated agreements.

The upcoming negotiations follow a visit by Ukrainian President Volodymyr Zelenskyy to Istanbul, where he held talks with Erdogan about the prospects of the grain deal and NATO membership.

"The whole world is interested in the functioning of the 'grain corridor,'" Zelenskyy said on Saturday at a joint press conference with Erdogan. 

"And it is very important that we start acting with our partners so that the life of the 'grain corridor' and therefore the lives of other people on other continents, including Africa and Asia, do not depend on the mood with which the Russian president woke up," he said. 

(With input from Reuters)

(Cover: A view of Port of Odesa, Ukraine, June 29, 2023. /CFP)