'Russian Arms Sales to Syria OK under International Law' - Putin's Spokesperson

What will Russia do in case chemical strike is confirmed to have been carried out by the Syrian government? Or, in another scenario, what will happen if the US follows on with their strike intentions even without solid proof of Assad's guilt, or without much international support or approval of such a strike? What will Russia's response be? We talk to Dmitry Peskov, press secretary for Russian President Vladimir Putin.