Against some expectations, Russia failed to veto sanctions on Iran while simultaneously canceling the pending sale of advanced anti-aircraft systems. Welcome to the new multi-polar world:

Moscow's policies towards the Middle East are clearly very different from its Cold War stance, when it steadfastly supported Muslim nations against the US and its closest ally, Israel.

Today Russia is seriously distressed by the spread of Western influence and the expansion of the North Atlantic Treaty Organisation (Nato) into what it considers its legitimate sphere of "privileged interests": Ukraine, Georgia and other former Soviet republics...

[I]f Israel obediently agrees to stop the supply of modern weapons to Georgia - like it did in 2008 - Russia is ready to be forthcoming on Iran.

The threat of Iran acquiring nuclear weapons is also a factor, but hardly the main one. The Russian military do not consider a handful of primitive North Korean or Iranian nuclear weapons a serious threat. Of course, Moscow has genuine business and security interests in the larger Middle East: supplying arms and nuclear technologies to Arab nations and to Iran.

At the same time, Russia has an increasingly important military and security relationship with Israel. With Israel, Russia has been jointly producing billions of dollars worth of weapons for India. The Russian military have acquired a substantial batch of different types of Israeli-made spy drones or unmanned aerial vehicle (UAV), the first official procurement of a major weapon system from a Western nation since 1945...

An additional factor that may further influence the decision-making in Moscow is Saudi Arabia's offer to buy more than $2bn worth of Russian weapons (helicopters, armour, anti-aircraft missiles) on condition that Russia does not sell Iran S-300 missiles, and stops supporting it in the UN.