Iran, Russia and Turkey have reached an agreement on setting up de-escalation zones in Syria, Russia media reported.

"The countries acting as guarantors of the Syrian ceasefire have reached a consensus on some memorandum provisions," TASS news agency quoted a source as saying.

"The work on the document is nearing completion."

Diplomatic delegations from Russia, Iran and Turkey arrived in the Kazakh city of Astana on Tuesday, to hold the fourth round of negotiations in pursuit of peace in Syria.

The peace initiative aims at bringing the Syrian government and the opposition groups to the negotiation table in order to put an end to the 6-year-long conflict in Syria.

"As you know, the Russian Federation is making intensive efforts to promote the Syrian peace settlement and is developing various schemes to strengthen the ceasefire agreement and make this agreement more effective," Russia’s special presidential envoy for Syria, Aleksandr Lavrentiev, said during a press conference after the first day of the peace talks in Astana.

Lavrentiev further said that the creation of de-escalation zones in Syria can help to move along the long-standing problem of separating the moderate Syrian opposition groups from terrorist organizations.

ISIS and Jabhat al-Nusra, among other terrorist groups, were not included in the peace talks.