Ukraine and Russia have made some progress in negotiations on grain exports that also involved Turkish and UN representatives in Istanbul, Ukrainian President Volodymyr Zelenskyy acknowledged on Wednesday.

"The Ukrainian delegation informed me that there is some progress. We will agree on the details with the UN secretary-general in the coming days," Zelenskyy was quoted as saying by his press service.

United Nations Secretary-General Antonio Guterres also hailed the progress as "a major step forward to ensure the export of Ukrainian food products through the Black Sea."

(With input from Xinhua)