Preliminary meetings with sides to the talks got underway on Thursday ahead of substantive talks expected Friday.
"There is a possibility that [negotiations] will begin with the discussion of the first and fourth 'baskets', that is the system of governance and the fight against terrorism," Moscow platform opposition member Nimrud Suleiman said.
Suleiman said constitutional and election issues would be addressed afterward.
"Apparently this is because of the priorities of the HNC [Riyadh-based High Negotiations Committee opposition] and Damascus delegations," he opined.
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