Turkey has seen "significant progress" in negotiations and is coordinating closely with Russia and Ukraine to agree on a plan that would restart grain exports from Ukrainian ports, Defense Minister Hulusi Akar said, even as conflict rages elsewhere in the country.

Turkey is involved in efforts by the United Nations to reach an agreement on a plan that would open a safe shipping corridor to address a global food crisis brought on by Russia’s invasion in February which halted Ukraine’s Black Sea grain exports.

Akar’s remarks came a day after reports suggested Ankara and Moscow had reached a tentative deal to restart shipments of Ukraine’s agricultural products, but Ukraine has yet to endorse the plan.

The issue of blocked grain will be on the agenda on Wednesday during Russian Foreign Minister Sergey Lavrov’s visit to Turkey.

Turkey is said to have offered military help to clear mines off the key Black Sea port of Odessa and escort grain ships. Kyiv worries that removing defenses could leave the port open to Russian attack.

Akar said the four sides are working out how mines floating off the port of Odessa and elsewhere along Ukraine’s coast will be cleared and who will do it, and who would safeguard the corridor.

"We are making efforts to conclude this as soon as possible," he told reporters in embargoed remarks after a Cabinet meeting late on Monday.

The parties are willing to resolve the issue, but mutual trust remains a sticking point, Akar said. "Everybody wants to be sure of certain things. We are working to establish such trust."

"A lot of progress has been made on this issue" and technical planning continues, the minister said.

In a phone call later on Tuesday, Akar discussed grain exports from Ukraine with his Russian counterpart Sergei Shoigu, Interfax news agency reported, citing the Russian defense ministry.

Lavrov visits Turkey

Turkey neighbors Ukraine and Russia at sea and has said it is ready to take on a role within an "observation mechanism" if a deal is reached.

Turkey has proposed establishing a center in Istanbul to coordinate and monitor demining efforts and shipments to global markets.

That could involve Turkish naval escorts for tankers leaving Ukraine and heading toward Turkey’s straits onward to world markets.

Agriculture and Forestry Minister Vahit Kirişci late Monday also said parties were close to agreeing on a deal on the corridor.

Kirişci also said Turkey and Ukraine had agreed on a 25% discount on grain products to be purchased from Ukraine, without elaborating.

Turkish Foreign Minister Mevlüt Çavuşoğlu will host his Russian counterpart Sergei Lavrov for talks on the plan on Wednesday.

Lavrov said Monday he was optimistic that military officials can work out a solution.

Western leaders have blamed Russia for holding the world for ransom by blockading Ukrainian ports. Moscow says Western sanctions are to blame for the situation.

Russia and Ukraine account for nearly a third of global wheat supplies, while Russia is also a big fertilizer exporter and Ukraine is a major exporter of corn and sunflower oil.

Nearly 25 million tons of grain stuck

As much as 25 million tons of grain are stuck in Ukraine awaiting shipment, a figure that Ukrainian President Volodymyr Zelenskyy on Monday said could triple by the autumn.

Only a maximum of 2 million tons a month could be exported if Russia refuses to lift its blockade, Taras Vysotskyi, Ukraine’s first deputy minister of Agrarian Policy and Food, said separately on Tuesday.

Ukraine exported up to 6 million tons of grain a month before Russia invaded the country, but in recent months the volumes have fallen to about 1 million tons.

Even if Russia’s port blockade is lifted, Vysotskyi said Ukraine would need about six months to demine the waters around its Black Sea ports, meaning the world would remain short of grains for some time.

Ukraine’s grain, oilseed and vegetable oil exports rose 80% in May to 1.743 million tons, but the volumes are still significantly below the exports in May 2021, the agriculture ministry said on Tuesday.

Zelenskyy on Monday asked for a secure corridor for Ukrainian vessels and said Kyiv is in talks with countries like Turkey and the U.K. about security guarantees for Ukrainian ships

He also said Kyiv is not ready to agree to a plan to export its grain by rail across Belarus for shipment via the Baltic Sea, an idea that was touted as a solution by Russian President Vladimir Putin.

Moscow assured Ankara it would not attack Odessa if the corridor is created, Presidential spokesperson Ibrahim Kalın said on Friday.

Separately, Russia said on Tuesday that two major Ukrainian ports on the Sea of Azov seized by Russian forces were ready to resume grain shipments, but the Kremlin said Kyiv still needed to demine the approaches to its ports for exports to take place.

Russian Defense Minister Shoigu said the ports of Berdyansk and Mariupol, the latter city destroyed after a three-month Russian siege, had resumed their operations.

"The demining of Mariupol’s port has been completed. It is functioning normally, and has received its first cargo ships," he said in televised comments.

Kremlin spokesperson Dmitry Peskov told reporters Ukraine still needed to demine its coast for grain exports to take place.

"This will allow ships, once checked by our military to make sure they are not carrying any weapons, to enter the ports, load grain and with our help, proceed to international waters," he said.