Russian President Vladimir Putin will host his Turkish counterpart Recep Tayyip Erdogan on Monday, the Kremlin said, amid hopes the two can restore a deal ensuring safe passage for grain shipments.

Russia pulled out from the UN-backed grain agreement that Turkey helped broker in July, effectively revoking safe navigation for civilian ships sailing through the Black Sea.

"Negotiations will indeed take place in Sochi on Monday," Kremlin spokesman Dmitry Peskov told reporters on Friday.

Moscow's announcement 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 Bosphorus," 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.

Turkey's foreign minister Hakan Fidan said on a visit to Moscow on Thursday that reviving the deal to ship Ukrainian grain across the Black Sea was "critical" for food security.

Turkey wants the warring sides to return to the agreement and use it as a basis for broader peace talks.

Moscow says the previous agreement imposed indirect restrictions on its grain and fertiliser exports by limiting Russia's access to global payment systems and insurance.

It has repeatedly said it could return to the deal if its demands are met.