"Date of the talks in Geneva is not officially established yet, we have not been informed about it yet," Hisham Marwah said.
He added that all the Syrian opposition parties had sent lists of their representatives to the body, which would shape the delegation for the talks with Syrian government, but the final list had not been created yet.
Syria has been mired in civil war since 2011, with forces loyal to Syrian President Bashar Assad fighting against numerous opposition factions and extremist groups.
Earlier this month, the UN Security Council adopted a resolution on Syrian reconciliation, which reaffirmed the goals of the Vienna agreements to bring the entire spectrum of the political groups in the crisis-torn country to the negotiating table and stated that the next round of the UN-sponsored intra-Syrian talks would take place in January, 2016.
On December 10, opposition groups from Syria formed a 32-member council tasked with choosing 15 delegates from numerous opposition groups to represent the Syrian opposition during talks with Damascus.
