Russian Federation is sending presidential envoy Alexander Lavrentiev, Iran is dispatching Deputy Foreign Minister Hossein Jaberi Ansari, while Turkey will likely send a Foreign Ministry department head to the Astana talks, according to officials.
The discussions were due to begin Wednesday and last two days, but were postponed until Thursday due to unexplained "technical reasons", Kazakhstan's foreign ministry said Wednesday. "I do hope that in the capital of Kazakhstan, where the Russian delegation has already arrived for working consultations due later today, an extra impetus will be given to an inclusive intra-Syrian dialog under the United Nations auspices in Geneva, which, we hope will be resumed in the last days of February".
The talks are likely to focus on bolstering a shaky ceasefire on the ground.
A new round of UN-backed peace talks is due to begin in Geneva next.
The worldwide meeting began on January 23 with the participation of a number of delegations, including armed opposition, Damascus, Russia, Iran, and Turkey.
While Kazakh officials said they invited both the Syrian government and rebels for the new talks, several members of the Syrian opposition who took part in the previous Astana talks told AFP that they have not received invitations. Jordan will also be represented by a "high-level delegation", government spokesman Mohamed Momani said.
Russia, Assad's most powerful ally, has sought to revive diplomacy since its air force helped to defeat rebels in Aleppo in December, the Syrian leader's biggest victory to date.
The first round of Astana talks on Syrian settlement was held in the Kazakh capital on 23-24 February 2017 with participation of delegations of Iran, Russia, and Turkey as observers and representatives of Syrian government and a number of armed opposition group.