Russia is pressing the Syrian leadership to honour previous pledges to enter talks with the opposition.
Foreign Minister Sergei Lavrov is warning that time is running out for the parties to save an accord reached by global powers in Geneva that calls for the introduction of a transitional government but makes no explicit call on Assad to step down.
UN Arab League envoy Lakhdar Brahimi yesterday pushed for the plan after several days of talks with the leadership and opposition representatives in Damascus.
After a meeting with the Syrian Deputy Foreign Minister, Lavrov said that "the chances for such a solution… are diminishing."
Russia has refused to back international pressure on Assad to step down and Lavrov says Moscow's position on this point had not changed.