Though there have been rumours of deployments of more Russian aircraft in Syria, and even some talk of the Russians building a second base in the north of Syria, there has been little in the way of hard evidence.

Today the Russian Defence Ministry has however now formally confirmed that SU35 fighters have been deployed to the Khmeimim airbase in Latakia.

The Defence Ministry does not appear to have said how many SU35 fighters have been deployed to Syria. However the Russian newspaper Kommersant - which earlier broke the story - says they number just four.

The SU35 is the most advanced fighter in Russia’s military arsenal. Like the four SU30 fighters already present at Khmeinim the SU35 has super-manoeuvrability. Unlike the SU30 it is a single seat fighter. It also has superior radar and electronics to the SU30.

By general acknowledgement, apart from the US F22 Raptor the SU35 is the most advanced and capable fighter in the world.

The decision to deploy the SU35 to Syria appears to be linked to more Turkish threats to shoot down Russian aircraft following Turkish claims - denied by Russia - that an SU34 violated Turkish airspace two days ago.

Based purely on information that has been publicly disclosed, there are now 16 highly capable Russian aircraft based in Syria all of which are fully capable of carrying out air to air missions and any one of which is more than a match for the F16s operated by the Turkish airforce.

These are now 4 SU35s, 4 SU30s and 8 SU34s deployed in Syria, based mostly at the Khmeimim base in Latakia, but apparently also occasionally flying from other Syrian bases as well.