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 fertilizer. The UN is trying to broker a deal to resume Ukraine grain exports and Russian food and fertilizer exports, which Moscow says are harmed by sanctions. “We are not responsible for establishing safe corridors. We…