UN Secretary-General Antonio Guterres on Sunday expressed “deep concern” as Ukraine’s maritime grain exports were halted after Russia suspended its participation in a deal that allowed the vital shipments. “The Secretary-General is deeply concerned about the ongoing situation regarding the Black Sea Grain Initiative,” his spokesman said. “He has decided to delay his departure for the Arab League Summit in Algiers by a day to focus on the issue.” Ukraine’s maritimegrain exports were halted after Russia suspended its participation, blaming drone attacks on its ships in Crimea. The July deal to u…