United Nations envoy on Syria Staffan de Mistura said he would not participate personally in Thursday's meeting but that his office would be represented by a "technical team". Talks will begin tomorrow.
The Kazakhstan talks are brokered by Russian Federation and Turkey, which back opposing sides in the war and have taken the lead with peace efforts since December.
At a first round of the Astana talks in January, Russia, Turkey and Iran, another Assad ally, reaffirmed a shaky ceasefire between insurgents and the Syrian government.
Russian Federation has maintained good ties with the Kurdish region, and pushed hard to include them in the Syrian talks aimed to end the six-year civil war, especially in Geneva, a move strongly opposed by Turkey and the HNC.
The talks in Geneva, the fifth time the parties have gone to Switzerland, have been pushed back twice already, in part to give the opposition more time to form a unified delegation.
"In theory, it is a complement to a still-live ongoing Geneva process", said Sam Heller, a non-resident fellow at The Century Foundation think-tank.
Turkey, Russia and Iran on Thursday agreed to set up a joint commission to supervise the Syria truce.
Turkey has sent a lower-level delegation to the talks, compared with the previous round, because some senior diplomats were accompanying President Tayyip Erdogan on a foreign visit, Lavrentiev said.
The Geneva talks, slated for February 23, are expected to bring together representatives from President Bashar Assad's government with exiled opposition figures and rebels fighting inside Syria.
Kazakhstan says it has postponed talks aimed at firming up a Syrian cease-fire by one day. Furthermore, the last summit in Astana failed to produce a breakthrough.
Erdoğan said that the Trump administration's attitude in the upcoming term as well as the support of Saudi Arabia and Qatar regarding the issue will play a key role. The opposition wants Assad to step aside, but the Syrian government says this is not something that is even on the table for negotiating.
The Syrian government also seems to be less open to negotiations following recent successes such as the full recapture of Aleppo at the end of a year ago.