Russia's air force announced on 30 November that its Sukhoi Su-24 and Su-34 combat aircraft operating in Syria have been armed with air-to-air missiles.

The development came less than a week after one of the former type was shot down by a Turkish air force Lockheed Martin F-16, and only days since Moscow deployed Almaz-Antey S-400 surface-to-air missiles to the conflict zone.

Tension continues to exist between Russia and Turkey following the Su-24's engagement, with Ankara refusing to apologise for the incident, which left one pilot dead.

With Russian combat aircraft expected to be operated while carrying defensive weapons such as Vympel R-27 medium- and R-73 short-range air-to-air missiles, the potential for an exchange of weapons is a "very realistic scenario", Israeli sources have cautioned.