In an interview last Friday by Webster Tarpley with Thierry Messan, the latter journalist, based in Damascus since the war began, has reported that, contrary to the usual sources, the announcement by Putin to withdraw from Syria was not a surprise to anyone involved, including Assad, and in no way indicates problems between Russia and Syria. In fact, there is a recent agreement between Obama and Putin, including Assad, to end the war in Syria, for the US to support the YPG Kurds there with weapons to fight ISIS since they defeated them in Kobane, who are now selling, and will continue to sell weapons to the PKK Kurds inside Turkey, and that Obama and Putin have agreed to cooperate for the end of Erdogan's rule in Turkey.
Messan says Turkey has fooled the EU on the refugee crisis because they have agreed to give him 3 BILLION Euro per year to keep the refugees/immigrants out of Europe. He says there was previously a deal between France and Erdogan, arranged by Juppe and Alland, to help Turkey created a Kurdistan in northern Syria, to where Erdogan would expel all the unwanted Kurds from Turkey, under the leadership promised to one of their own. However, when the USA changed its policy toward Turkey's involvement in Syria last summer, France chose to follow the new US policy and reneged on its agreement with Erdogan, for which it is likely that he arranged the Nov. 13 Paris attacks as a response, according to Messan.
And according to Messan, Erdogan is the prime suspect in the Brussels bombings last week following his March 18 speech specifically warning Brussels of the likelihood of being bombed, and accusing them (Belgium and Europe) of terrorism for supporting the PKK Kurds inside Turkey. This was followed on Mar. 24 by Erdogan's saying the bombings were just punishment.
Messan characterizes the current situation as Obama and Putin cooperating against the EU, who are, at some level, keen to regain influence over the Middle East in Libya and Syria. In that context, the direct communication between Obama-Putin / Kerry-Lavrov is superseding those who have enabled the Syrian Civil War.
DISCLAIMER: I think a lot of what Messan reports checks out, but his report last year about Russian electronic countermeasures demoralizing a
US Navy ship so badly that 27 resigned was never confirmed, nor was the claim that all NATO communications could be stopped by Russia. It takes lots of news sources to get any kind of balance picture of far away, complicated events.