UN-backed peace talks for war-ravaged Syria were set to resume in Geneva Tuesday, but without Syrian government negotiators, who sources said have yet to determine if they will return.
"The delegation will not leave today or tomorrow for Geneva, and the final decision (on attending) has not been taken yet," a source close to the government delegation told AFP on Tuesday.
An eighth round of peace talks aimed at ending Syria's nearly seven-year war began in Geneva last week.
UN Syria envoy Staffan de Mistura announced shortly after the talks began that they would be extended by two weeks.
Negotiations were paused over the weekend, but both sides were expected to return to Geneva to resume discussions on Tuesday.
A UN spokeswoman said the talks would indeed resume Tuesday as planned.
"The Special Envoy has announced last week a recess. This recess (ends) today," Alessandra Vellucci told reporters in Geneva.
However, the Al-Watan newspaper, which is close to the government, said the regime's delegation was in Damascus and was not expected to leave either Tuesday or Wednesday.
The daily said the invitation to return to the talks "is still being studied by the Syrian leadership".
When asked about the delay, Vellucci said the government delegation had "been invited back in Geneva as of today (Tuesday). The Special Envoy stands ready to engage them when they return."
"We expect and we hope they will be here very soon," she added.
Meanwhile, the opposition delegation to the talks said its head Nasr al-Hariri had arrived in Geneva and would meet de Mistura on Tuesday afternoon.
On Monday, a government source had already cast doubt on the return of the delegation to the talks.
"For the time being there has been no final decision. Damascus is still thinking about the feasibility of its participation," the government source told AFP, speaking on condition of anonymity.
"As soon as a decision is reached, it will be made public through the usual diplomatic channels."
The government delegation left Geneva on Saturday, after its chief negotiator Bashar al-Jaafari said there were "big problems in this round of talks".
He was referring to a communique published by the opposition last month in Riyadh signalling that it was maintaining its insistence on President Bashar al-Assad's removal.
The opposition, united in one delegation for the first time, has defied calls to give up on its demand that Assad must step down before any peace deal can be reached.
Jaafari described that position as "provocative" and "irresponsible", warning that "there will be no progress" if the opposition maintained that position.
De Mistura has tried to maintain an upbeat note on the talks, and on Friday he published a document suggesting 12 principles for a future Syria that he suggested the two sides could agree, including that the country "shall be democratic and non-sectarian".
He asked the parties to discuss the points and add their thoughts before the talks resumed.
More than 340,000 people have been killed in Syria since the conflict began with anti-government protests in March 2011.