"This question presupposes the goodwill of the US and its allies … I believe the only way to convince the US and its allies to withdraw is to demonstrate to them that their continued presence will be detrimental to their own interests," Moustapha said.
The diplomat noted that the United States' recent history never provided a single instance of goodwill or desire for constructive engagement with others.
"Their withdrawal from Syria is a requirement not contingent on any other circumstance. They have actually abetted the terrorist groups and helped further undermine the Syrian government’s efforts to fight against the most radical of these groups," Moustapha noted.
The diplomat highlighted that when the majority of terrorist groups are either defeated or evacuated to the northern parts of Syria, more serious efforts can focus on the political process.
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Assad, during his meeting with Putin, announced that he would be sending his delegation to take part in forming the Constitutional Commission in the United Nations.
The settlement process for the Syrian conflict, which broke out in 2011, has been discussed on a number of international platforms, such as those in Geneva and Astana and the Syrian National Dialogue Congress in Russia's Sochi. The main result of the Sochi congress was the creation of the Constitutional Commission that would work in Geneva and focus on amending Syria's existing constitution.