A fresh round of Syrian peace talks is scheduled for mid-June in the Kazakh capital, Syria's envoy to Moscow said Saturday, with sponsors Russia, Iran and Turkey aiming to bolster safe zones in the country.
Ambassador Riyad Haddad told Russia's state-run RIA Novosti agency that Damascus had "received an invitation to participate in talks in Astana, to take place on 12-13 of this month".
Two rebel sources said they had not yet received an invitation.
Moscow, a key backer of the talks, had earlier said it wanted a fresh round mid-June but has not given firm dates. Host Kazakhstan said it could not "confirm or deny" the talks were scheduled.
At the last round of negotiations in May, regime backers Moscow and Tehran and rebel supporter Ankara agreed to establish four "de-escalation zones" to ease fighting in opposition areas.
The zones -- where aerial bombardments were supposed to stop -- have ushered in a marked decrease in fighting on the ground, but there remain key outstanding issues to negotiate.
The three powers have until Sunday to come up with proposals for definitive boundaries and are still wrangling over which countries should send in forces to police the safe zones.
Moscow has spearheaded the talks in Astana since the start of the year as it tries to turn its game-changing military intervention on the ground into a negotiated settlement.
The tetchy negotiations -- seen as a complement to broader U.N.-backed talks in Geneva -- have involved armed rebels and government officials and have focused mainly on military issues