Russia has violated NATO-ally Bulgaria's airspace 10 times in the last month in what the country's minister of defense has described as provocation, Bulgarian national TV channel Nova TV reports.
"The entry of Russian aircraft in our zone of exclusivity is provocation with an unclear goal," Nenchev said. "This is highly worrying, which is why we are undertaking preventive measures."
Nenchev did not specify what these measures were, however he vowed that Bulgarian jets were ready to intercept any Russian aircraft if needed, but said this was wasteful of Bulgaria's resources.
"You know very well that we do not provoke anyone in any form, but when there are foreign airplanes, flying inside our zone of exclusivity with their transponders switched off. This is highly concerning and we undertake all necessary procedures."
Nenchev said he had received no explanation for the incursions but that the conversation was conducted between Bulgaria and Russia's foreign ministry diplomats. According to him, four of the 10 aircraft were military ones.
The rift between Russia and the West has been highly uncomfortable for Bulgaria's government, one of the eastern-most members of the EU and NATO. The country's shared history with Russia, dating back to Bulgaria's Russian-led liberation from the Ottoman Empire, means many Bulgarians still view Moscow in a positive light.
Last month Bulgaria's Prime Minister Boyko Borisov ruled out taking part in a NATO Black Sea force, proposed by Romania and Turkey in response to the fleet Russia is assembling off the coast of annexed Crimea.
