Regarding Moscow’s statement that it has not received any protest from the Bulgarian side regarding violations by Russian aircraft over the Black Sea, the Bulgarian Ministry of Defence declares that the information it made public did not refer to violations of Bulgaria’s air space, which would require a formal protest but to violations inside the Flight Information Region Sofia (FIR Sofia). Inside this region the Bulgarian air force and NATO have registered flights by Russian aircraft with their transponders off, without prior notification of their flight plans, and one instance of an airplane flying with no identification markings. While it does not deny the right of military aircraft of other countries to fly in international airspace over the Black Sea, Bulgaria wants to see international air navigation rules respected, the Bulgarian Defence Ministry statement reads.