GENEVA --United Nations envoy Lakhdar Brahimi appeared to have averted the collapse of peace talks Friday between Syria's government and opposition after a fraught first day, saying in late afternoon that the two sides have agreed to meet face-to-face on Saturday.

After threats by the Syrian government to abandon the long-awaited talks because the opposition delegation refused to meet in the same room as its foe, Brahimi said he had secured the commitment of the two sides to sit down together.

Brahimi seemed confident that neither side would walk out, at least in the coming days, and he predicted that the talks would continue for another week before taking a break.

"Both parties are going to be here tomorrow; they will be meeting," he said. "We will be working on Saturday; we will be working on Sunday. Nobody will be leaving on Saturday, and no one will be leaving on Sunday."

"We do expect some bumps on the road," Brahimi added. "It is impossible that there aren't any."

If the meeting goes forward, it will be the first face-to-face session between the warring factions since the start of a bloody civil war that has left more than 130,000 people dead.

The delegation representing opposition groups said earlier Friday that it would not enter into direct talks unless the government agreed that the purpose was to negotiate a transitional government to replace the regime of President Bashar Assad.

Hearing that, the government delegation threatened to go home.

Opposition representatives said they want Assad's representatives to sign the protocol under which the talks are being held before they meet with them. The so-called Geneva I communique specifies that the talks, known as Geneva II, should negotiate the formation of a transitional government that would strip Assad of his authority.

The Syrian government said it would not sign the protocol, stressing that it had agreed to attend the Geneva talks "without preconditions," according to a journalist traveling with the government delegation.

In a speech at the World Economic Forum in Davos, Secretary of State John Kerry said Friday that despite the setbacks, the U.S. continues to believe that a peaceful, pluralistic Syria "is achievable" and that "it is ultimately diplomacy" that will end the conflict. "There is no military solution to the problem of Syria," he said.