Anja Neidringhaus / AP
Anas al-Abdeh, a member of Syria's main political opposition group, is surrounded by journalists after a meeting with a delegation of the Syrian government at the U.N. headquarters in Geneva on Saturday.
GENEVA -- The first meeting between leaders of the Syrian government and the opposition attempting to topple President Bashar Assad on Saturday was a tense and silent stare-down that lasted only 30 minutes, prompting the U.N. mediator overseeing the talks to acknowledge that "we haven't achieved much."
After tense days spent avoiding each other and meeting separately with the mediator, Lakhdar Brahimi, Assad's handpicked delegation and representatives of the Syrian National Coalition gathered briefly at a single U-shaped table, then emerged and went separate ways, using different doors to avert contact.
The only speaker in the talks aimed at ending Syria’s nearly 3-year-old civil war was Brahimi, who laid out a rough roadmap for the discussions, which will continue on Sunday.
"We haven't achieved much but we are continuing," he said at a news conference after two meetings at U.N. headquarters in Geneva.
Brahimi said the first two items up for discussion would be getting aid supplies to the besieged city of Homs and arranging a release of prisoners by both sides.
He expressed hope that a deal on the aid for Homs could be reached quickly, saying a humanitarian convoy could move into Homs as early as Monday if the negotiators OK it on Sunday.
Members of the SNC delegation said it was difficult sitting opposite members of the Assad regime.
"It was not easy for us to sit with the delegation that represents the killers in Damascus but we did it for the sake of the Syrian people and for the sake of the Syrian children," said Anas al-Abdeh, who was among the coalition's representatives. He said everyone remained calm.
Despite the evident tensions, opposition spokesman Louay M. Safi told NBC News that negotiations on forming a transitional government would begin Monday.
“The regime will need to commit themselves,” he said. “They are trying to find a way out by fabricating excuses.”
Safi’s claim was not immediately confirmed by he Syrian government delegation or U.N. officials.
The two sides were distant going into the meeting, with the Damascus delegation denying it had accepted the premise of a transitional leadership, and the opposition saying it would accept nothing less than President Bashar Assad's departure. Still, diplomats have said even getting them to the same table can be considered an accomplishment, almost three years into the uprising that has killed 130,000 people.
Syrian Information Minister Omran al-Zoubi, said right before the talks started that there was still an "enormous gap" in how the two sides interpreted a transitional government.
"Those who talk about President Bashar Assad are talking about removing the man who is leading the war against terrorism," he said.
First on the agenda was a cease-fire in the city of Homs, Syria's third-largest city. Neighborhoods in the old city have been ravaged following repeated government assaults to reclaim control from rebels. The city had a pre-war population of 1 million, but most residents have since fled.
Homs was one of the first areas that plunged into armed conflict in 2011 after Assad responded to largely peaceful protests by unleashing the military. A quarter of the country's population has been displaced, taking refuge from the fighting in camps across the borders or within Syria. Meanwhile, a homegrown rebellion has transformed into a regional proxy war between Iran and Saudi Arabia, with foreign fighters flooding in on both sides.
State Department spokesperson Edgar Vasquez, who is in Geneva for the talks, said that members of the opposition have displayed "the intention to engage constructively” in the early sessions.
Separately, a U.S. official who spoke with NBC News on condition of anonymity criticized some key members of the Syrian government delegation for skipping Saturday’s meeting.
“The expectation was that the entire regime delegation would be at the table today,” the official said. “The regime's actions, when compared to that of the opposition, further prove that they do not represent the best interests of the Syrian people, who deserve real negotiations to end the war and the suffering. Today, as innocent civilians die in Syria, the regime continues to play games.”
NBC News' Catherine Chomiak and The Associated Press and Reuters contributed to this report.