Syria Russia relationship 'still firm' says BBC's Bowen

World leaders from the G20 group of nations are preparing to meet in St Petersburg in Russia.

The summit is officially about global economic matters but Syria is likely to dominate proceedings.

Ahead of the talks, Russia's President Vladimir Putin warned that action without UN approval would be "an aggression".

But President Barack Obama said the credibility of the international community was on the line.

Jeremy Bowen is one of the few international broadcasters in Damascus. He said ties between Russia and Syria remain strong.