Assad "stressed the importance of efforts exerted by the friendly and allied countries of Syria, particularly Iran and Russia" as he met Hossein Jaberi Ansari, a senior adviser to the Iranian foreign minister, in Damascus Sunday.
The UN-backed constitutional committee will include 50 members chosen by Damascus, 50 by the opposition and 50 by the United Nations. The constitution will pave the way for elections aimed at turning the page on seven years of war.
The opposition is reportedly pushing for an entirely new constitution, but Damascus has said it will only discuss altering the current one, Presstv Reported.
On Sunday, Assad called for an end to "the interference of some Western states in the political track and consolidating the establishment of a political process led by the Syrians themselves away from any form of external intervention."
Turkish Foreign Minister Mevlut Cavusoglu and his Russian counterpart Sergei Lavrov said Friday that the make-up of the committee was nearly complete.
According to Lavrov, Turkey, Russia and Iran will present the list of candidates for the Syrian Constitutional Committee to UN Special Envoy for Syria Staffan de Mistura this week.
Turkey, which backs militants fighting to topple the Assad government, has deployed troops into Syrian soil without permission from Damascus which has denounced it as an act of aggression.
On Sunday, Cavusoglu said Turkey will consider working with President Assad if he wins a democratic and credible election.
Assad acknowledged Iran's efforts towards the formation of the committee on discussing the new constitution "in spite of the big obstacles put by states which support terrorism."
Jaberi Ansari, for his part, briefed Assad on preparations made for a pending meeting among the three guarantor states in Geneva.
He also affirmed Iran’s commitment to continued consultation and coordination with Damascus.