Inspections of ships carrying Ukrainian grain from the Black Sea resumed on Wednesday under a UN-brokered deal, but Kyiv said more time was needed to secure an extension of the initiative.
Ukraine, which depends heavily on revenue from grain sales as it battles Russia's invasion, and its allies blamed the latest halt to ship inspections in the Bosphorus on Moscow, which in turn has blamed Ukraine and the United Nations.
Ukrainian Deputy Prime Minister Oleksandr Kubrakov wrote on Facebook that "ship inspections are being resumed, despite the RF's (Russian Federation's) attempts to disrupt the agreement".
The Joint Coordination Center in Istanbul that oversees operations said "inspections are already at work".
Talks on extending the Black Sea grain deal beyond a May 18 deadline have not produced a breakthrough, and Kyiv's grain exports are also restricted by import bans imposed by three eastern European countries.
The Black Sea Grain Initiative, reached with UN and Turkish mediation last July, unblocked three Ukrainian Black Sea ports five months after Russia's invasion.
It was designed to alleviate a global food crisis as well as to support Ukraine whose economy relies heavily on agricultural exports.
Russia's Foreign Ministry, without offering documentary evidence, accused Kyiv of sabotaging the deal by demanding bribes from ship owners to register vessels and carry out inspections. Kyiv did not immediately comment on the allegation.
Russia says it has committed to the initiative only until May 18, and complains a separate deal meant to ease its own agricultural and fertilizer exports has not been upheld.
Ukrainian Agriculture Minister Mykola Solsky told reporters talks were taking place to get the deal extended next month. But making clear no immediate breakthrough was expected, Solsky said: "Let's give them time."
He gave no details of the talks. Russian Foreign Minister Sergei Lavrov is due to discuss the grain export deal with UN Secretary-General Antonio Guterres in New York next week.
Import bans
Kyiv is also trying to secure agreement from three European Union members states in eastern Europe to lift bans on Ukrainian grain and food products.
Hungary, Poland and Slovakia have imposed bans to protect their markets from an influx of cheaper supply following the Russian invasion of Ukraine, and Bulgaria and Romania have said they could also take action.
Poland went further by banning not just imports, but also the transit of Ukrainian grain through its territory. It agreed on Tuesday to lift the transit ban after talks with Kyiv.
Large quantities of Ukrainian grain have been trapped in eastern and central Europe as low global prices and demand meant grain cannot easily be sold on.
The bottlenecks reduced prices and sales by local farmers, putting political pressure on governments in the region.
The EU has criticized member states for putting individual bans in place, and EU ambassadors were expected to discuss the situation in Brussels later on Wednesday.
European trade commissioner Valdis Dombrovskis was also due to have a video conference on Wednesday with trade ministers from Bulgaria, Hungary, Poland, Romania and Slovakia.
The European Commission, the EU executive, has said it is considering a second package of farmer compensation payments following an initial 56- million-euro ($61 million) package agreed for Bulgaria, Poland, Romania at the end of March.
