President Recep Tayyip Erdoğan is set to fly to the Black Sea resort of Sochi on Monday for a summit with his Russian counterpart Vladimir Putin, just over six weeks after Moscow broke off a deal that allowed Ukrainian grain to reach world markets despite the 18-month war.

The talks, announced by Kremlin spokesperson Dmitry Peskov on Friday, end weeks of speculation about when and where the two leaders might meet next as efforts continue to patch up the Black Sea Grain Initiative which got grain and other food to Africa, the Middle East and Asia where hunger is a growing threat.

Türkiye was the main sponsor of the U.N.-backed agreement secured in July 2022, using its good relations with both Moscow and Kyiv to help strike the only major deal reached by the sides during the war. The initiative allowed Ukraine to ship grain and other foodstuffs from three Black Sea ports.

A separate memorandum between the U.N. and Russia, agreed at the same time, pledged to overcome obstacles to Moscow's shipment of food and fertilizer to world markets.

The deal followed Russia's Feb. 24, 2022, invasion of Ukraine which sent global food prices skyrocketing because the two countries are major "breadbaskets" for the world.

However, Russia pulled out of the deals in mid-July, claiming that its conditions hadn't been met.

Before the leaders' summit, Foreign Minister Hakan Fidan arrived in Moscow on Thursday for talks with his Russian counterpart Sergey Lavrov. Fidan stressed that reviving the grain was "critical" for food security.

"We underlined its critical role for global food security and stability in the Black Sea," the top diplomat told a joint media appearance with Lavrov.

Lavrov said he had given Ankara a list of actions the West would have to take in order to resume Ukrainian grain and fertilizer shipments. Talks between Erdoğan and Putin could help unlock that.

Meanwhile, the U.N. chief on Thursday said he had sent Russia a new proposal aimed at getting its grain and fertilizer to global markets in hopes of reviving the deal that allowed Ukraine to ship almost 33,000 tons of grain at a time of growing global hunger.

But Moscow wasn't satisfied with the letter that U.N. Secretary-General Antonio Guterres sent Lavrov earlier this week.

Lavrov said Russia saw no sign that it would receive the guarantees needed to revive the deal.

Guterres told U.N. reporters on Thursday that he had written a letter to Lavrov with "a set of concrete proposals, allowing to create the conditions for the renewal of the Black Sea initiative."

He did not give any details other than to say, "we have some concrete solutions for the concerns allowing for an effective, or more effective access of Russian food and fertilizers to global markets at adequate prices."

Moscow repeatedly complained that the Ukraine deal largely benefitted richer nations, and that Russia still had difficulties obtaining financing, insurance and shipping for its fertilizer and grain shipments.

Data from the Joint Coordination Center (JCC) in Istanbul, which organized the Ukraine shipments, shows that 57% of the grain from Ukraine went to developing nations, with the top destination being China, which received nearly a quarter of the food.

Fidan told reporters his meeting with Lavrov in Moscow was "preparation" for the upcoming summit between Erdoğan and Putin.

Türkiye has positioned itself to facilitate any peace talks between Ukraine and Russia. It has opposed the Russian invasion but also the Western sanctions on Moscow.

Erdoğan has maintained good relations with Putin and helped broker prisoner exchanges between the warring sides.

The Turkish leader has repeatedly called on the Western countries to consider Russia’s demands and said he hoped his talks with Putin could lead to the restoration of the Black Sea initiative.

Describing the grain deal as "quite a complicated and laborious job," Fidan said when the two leaders get together they "will take a more strategic and political view."

Since Russia exited the agreement, both it and Ukraine have issued warnings and carried out attacks on vessels off their coasts, stirring worries that commercial shipping could grow riskier across the entire sea.

While Ukraine and some other Western states have promoted alternative routes for Ukrainian exports, Ankara opposes them on safety grounds. It wants the West to accept some Russian demands, and for Russia to drop others, to restart Ukraine grain exports under U.N. and Turkish oversight.

Moscow's announcement on Friday came shortly after Ukraine said two more ships were sailing through a temporary corridor Kyiv had set up to ensure safe navigation.

"Two vessels are sailing through a temporary corridor from Ukraine's Black Sea ports to the Bosporus," Infrastructure Minister Oleksandr Kubrakov said on social media.

Kyiv announced the new maritime corridor in August after Moscow warned ships leaving Ukraine's ports could be considered military targets.

Lavrov told reporters: "As soon as talks turn into concrete decisions, we'll be ready to resume the Ukrainian part of the grain package that same day."

One of Moscow's main demands is for the Russian Agricultural Bank to be reconnected to the SWIFT international payments system. The EU cut it off in June 2022.

While Russian exports of food and fertilizer are not subject to Western sanctions imposed after Russia's invasion, Moscow has said restrictions on payments, logistics and insurance have hindered shipments.

The U.N.'s Guterres said a renewed Black Sea initiative must be "stable" – and not move "from crisis to crisis, from suspension to suspension." The original agreement for 120 days was extended once for 120 days and twice for 60 days.

"I believe that working seriously we can have a positive solution for everybody – for Ukraine, for the Russian Federation, but more important than everything else for the world in a moment in which so many countries are facing enormous difficulties in relation to guarantee the food security of their populations," he told reporters.