Talks between the Syrian government and armed opposition will begin in Astana on Monday to last for two days.
The Kremlin excluded former Secretary of State John Kerry from Syria negotiations sponsored by Moscow and Ankara at the end of past year.
The main objective of the inter-Syrian talks in Astana would be confirming of the agreements on ceasefire in Syria of 29 December, 2016, sources close to the talks told TASS on Sunday.
Ibrahim Biro, head of the Kurdish National Council (KNC or ENKS), Abdulhakim Bashar, deputy president of the Syrian National Council, and Darwesh Mirkan, as a consultant, have been fingered by Ankara to be in Astana, but it was unclear if they would directly participate in talks.
The opposition delegation, which mainly comprises Turkey-backed militant groups, was expected to depart for Astana on Saturday.
The US will not send a special delegation to the Syria talks, which are due to be held in the Kazakhstan capital, Astana on January 23, according to the US State Department.
Russian Federation and Iran back the Syrian government forces under President Bashar al-Assad, while Turkey and the United States have supported rebels who want to see him removed from power.
Russian Federation and Turkey had supported the idea of a USA delegation to attend the talks.
Assad summarized that "terrorist groups", referring to rebels, need to disarm.
He said the conference will be in the shape of negotiations between the government and the rebel groups to reach a ceasefire and allow the rebels to join the reconciliation deals with the government.
Several rounds of United Nations and USA brokered talks have so far failed to bring any lasting respite in Syria's war, which the United Nations estimates has displaced half the population from their homes and killed more than 400,000 people.
Previous ceasefire attempts involving the United States and United Nations quickly fell apart as the warring sides exchanged fire and blame.