Russia said on Wednesday it has offered “safe passage” for Ukraine grain shipments from the country’s Black Sea ports, but is not responsible for establishing the corridors, as Turkey suggested that ships could be guided around sea mines.

Ukrainian grain shipments have stalled since Russia's invasion and ports blockade, stoking global prices for grains, cooking oils, fuel and fertiliser. The UN is trying to broker a deal to resume Ukraine grain exports and Russian food and fertiliser exports, which Moscow says are harmed by sanctions.

“We are not responsible for establishing safe corridors. We said we could provide safe passage if these corridors are established,” Russia’s UN ambassador Vassily Nebenzia said.

“It’s obvious it’s either demine the territory, which was mined by the Ukrainians, or to ensure that the passage goes around those mines,” he told reporters at the UN.

Turkish foreign minister Mevlut Cavusoglu said earlier on Wednesday that it would “take some time” to de-mine Ukraine’s ports and a safe sea corridor could be established in areas without mines under a UN proposal.