Mark N. Katz is a professor of government and politics at George Mason University (Fairfax, Virginia, USA), and is the author of Leaving without Losing: The War on Terror after Iraq and Afghanistan (Johns Hopkins University Press).

(CNN) -- As numerous news organizations have reported, Russia has sent two planes so that about 100 of its citizens who want to can leave Syria. Tellingly, the planes were not sent to Damascus where the security situation around the airport has reportedly deteriorated, but to Beirut instead to which the Russians departing Syria traveled by bus.

In its characteristic fashion, the Russian government has denied that this is an evacuation. An unnamed Russian diplomat in Damascus, though, did not rule out the possibility of further flights. Russian naval exercises in the Mediterranean may also be the prelude to a seaborne evacuation from the Syrian coast.

These actions are not the first indication that Moscow expects the Assad regime may fall. Russian Deputy Foreign Minister Mikhail Bogdanov acknowledged this possibility in December, and President Vladimir Putin himself seemed to distance himself from President Bashar al-Assad a week later. Arranging for the emergency departure of Russian citizens from Syria though, is the most serious indication to date that the Kremlin is preparing for the further weakening or even the downfall of the Assad regime....