The Romanian president, Klaus Iohannis, said that if the wreckage was confirmed to be Russian, it would be “a serious violation” of a NATO member’s sovereignty.
Ukraine’s Danube River ports have become key arteries for grain exports. But threats from Russia and costly delays have made some shippers rethink their operations in the Black Sea.
The announcement came on the same day that a cargo ship stranded in the Odesa port became the first to venture into the turbulent waters of the Black Sea despite Moscow’s threats to treat vessels in the area as hostile.
A 40-mile channel, best known outside shipping circles as a magnet for bird watchers, is now a crucial route allowing Ukrainian grain to reach the sea, protected by a NATO umbrella.