The Bulgarian government Wednesday allowed 12 US aircraft to temporarily guard the country's airspace under the integrated NATO air defence system.
The US aircraft will conduct limited missions together with the Bulgarian Air Force during the joint flight training "Thracian Eagle 2014" which will end Sep 12, Xinhua reported.
The missions will consist of aerial surveillance and visual identification, creating conditions for increasing the interoperability of air defence of the two countries, Government Information Service (GIS) in Bulgaria said.
Bulgaria has been a NATO member since 2004. Soviet-made MiG-29 and MiG-21 fighters make up the backbone of its current air defence.