Russia on Saturday suspended participation in the UN-brokered Black Sea grain deal after what it said was a major Ukrainian drone attack on its fleet and civilian ships at the Sevastopol base.
Russia's Defense Ministry said Ukraine attacked the Black Sea Fleet near Sevastopol with 16 drones early on Saturday, and claimed British navy "specialists" had helped coordinate the "terrorist" attack.
Britain on Saturday said Russia's claims were false. Ukraine neither confirmed nor denied carrying out the attack, but described Russia's decision to halt the grain deal as "primitive blackmail."
Ukraine's President Volodymyr Zelenskyy said Russia's "nonsensical" move required a strong international response from the UN and the Group of 20 (G20) major economies.
"This is a completely transparent attempt by Russia to return to the threat of large-scale famine for Africa, for Asia," Zelenskyy said in a video address, adding that Russia should be kicked out of the G20.
U.S. President Joe Biden denounced the move as "purely outrageous" and said it would increase starvation.
The Russian side told UN Secretary General Antonio Guterres in a letter, according to Reuters, that it was suspending the deal for an "indefinite term" because it could not "guarantee safety of civilian ships" travelling under the pact. Russia has also asked the UN Security Council to meet on Monday over the attack, Russia's Deputy UN Ambassador Dmitry Polyanskiy wrote on Twitter.
Russia said it had repelled the attack but that the ships targeted were involved in ensuring the grain corridor out of Ukraine's Black Sea ports.
Ukraine's Foreign Minister Dmytro Kuleba said Moscow was using a false pretext to sink the deal. In a statement, the European Union said "all parties must refrain from any unilateral action that would imperil" a deal it described as a critical humanitarian effort.
Since Russia and Ukraine signed the UN-backed Black Sea Grain Initiative in Türkiye on July 22, more than 9 million tonnes of corn, wheat, sunflower products, barley, rapeseed and soya have been exported.
But Russia has repeatedly alleged that rich Western countries were taking the grain exported from Ukraine, instead of allowing it to be delivered to the world's poorest countries as originally intended.
The United Nations is in contact with Russian authorities about the situation, a UN spokesman said.