Syrian fighters attend a mock battle in anticipation of an attack by the regime on Idlib province and the surrounding countryside, during a graduation of new Hayat Tahrir Al Sham (HTS) members at a camp in the countryside of the northern Idlib province last August/ AFP

Moscow, Beirut, London - Raed Jabr, Asharq Al-Awsat

An informed Russian source told Asharq Al-Awsat on Friday that Moscow has already launched “calm efforts to open communication channels between Tel Aviv and Tehran with an aim to lower tension and prevent a possible confrontation between the two sides in Syria,” particularly after Russia completed the delivery of S-300 missile system to Damascus.

The source did not rule out that Russia plays the role of a “mediator” between the two sides in that regard.

Meanwhile, in Moscow, Deputy Foreign Minister Sergei Ryabkov said that “Damascus has the right to defend its territories,” adding that the delivery of S-300 missile system to Damascus aims to “promote stability and is not a provocative act.”

However, the French Foreign Ministry said on Friday it was “concerned” by Russia's delivery of advanced anti-aircraft defense system to Bashar Assad's army.

Foreign Ministry spokeswoman Agnes von Der Muhll told reporters in an online briefing, “France notes with concern the delivery by Russia of sophisticated anti-aircraft capabilities for the benefit of the Syrian regime.”

She added that "Amid regional tensions, the delivery of such equipment by Russia contributes to maintaining the risk of military escalation and removing the prospect of a political settlement of the Syrian crisis.”

Separately, the Syrian Observatory for Human Rights said Friday fighting began between Hayat Tahrir al-Sham (HTS), led by former Al-Qaeda militants, and a faction from the National Liberation Front in the countryside of Aleppo near a planned demilitarization zone.

Last month, Russia and Turkey agreed last month to set up a demilitarization zone in Idlib that would be free of both heavy weapons and jihadists.

The Britain-based Observatory said HTS had taken two towns, including Kafr Halab. At least three civilians, one HTS member, and two NLF fighters were killed, the monitor said, according to AFP.