A Turkish military delegation will visit Russia to hold talks on a potential grain export corridor in the Black Sea, presidential sources said Tuesday, adding that a four-way summit in Istanbul will be held in less than 10 days.

President Recep Tayyip Erdoğan and U.N. chief Antonio Guterres might attend the meeting in Istanbul, the sources told Habertürk.

The TASS news agency cited the Kremlin on the same day as saying that Russia's defence ministry will hold talks with Turkey about the possible creation of a Black Sea corridor for Ukrainian grain supplies.

President Vladimir Putin does not plan to take part in these talks, Kremlin spokesman Dmitry Peskov said.

Ukrainian grain shipments have been stalled since Russia’s invasion and ports blockade, stoking global prices for grains, cooking oils, fuel and fertilizer. The United Nations has appealed to the two sides, as well as to their maritime neighbor and NATO member Turkey, to agree on a corridor. It is trying to broker a deal to resume Ukraine exports and Russian food and fertilizer exports, which Moscow says are harmed by the sanctions.

Foreign Minister Mevlüt Çavuşoğlu on Wednesday detailed the U.N. plan to create a sea corridor for Ukrainian agricultural products, suggesting that ships could be guided around the floating naval mines.

His comments appeared to mark a shift from an earlier proposal to demine Ukraine’s ports, a move that Kyiv fears would leave it far more vulnerable to Russian attack from the Black Sea.

Ukraine fears that demining its ports would leave it far more vulnerable to Russian attack from the Black Sea.

Moscow denies responsibility for the food crisis, blaming Western sanctions.

Turkey, which has the second-biggest army in NATO and a powerful navy, has good relations with both Kyiv and Moscow and has said it is ready to take up a role within an "observation mechanism" based in Istanbul if there is a deal.