Syria's long-awaited peace talks, set to start Friday in Geneva, have been thrown in doubt as a Saudi-based opposition group appears hesistant to attend.
The United Nations has said that the internationally backed negotiations will go ahead as scheduled on Friday.
But the opposition's Saudi-based Higher Negotiations Committee said it would not go to Geneva and would hold further internal discussions Friday in the capital Riyadh to make a final decision on participating in the UN-sponsored talks.
Key members of the opposition have been indicating their participation may hinge on the Syrian government stopping airstrikes and lifting its siege on towns inside the war-ravaged country.
The head of the committee, Riyad Hijab, said that the panel's members "do not see prospects for these negotiations."
"We are not going to the negotiations because the discussed agenda is not accepted by us. We had earlier said [during the previous talks] that we do not want any role for [Syrian President] Bashar al-Assad in the future Syria," Hijab told Dubai-based television Al Arabiya late Thursday.
World powers hope that the Geneva negotiations will initiate a political process to resolve Syria's conflict that started as peaceful anti-government protests in 2011 and is estimated to have cost the lives of more than 250,000 people.
The Islamic State terrorist militia has taken advantage of Syria's strife and has seized large areas of the country.