The first talks between Syria's warring sides were off to a rough start on Friday after the United Nations failed to convince regime and opposition delegates to sit in the same room.
Pulled together by the UN, Russia and the United States, delegations from President Bashar al-Assad's regime and the opposition had been due to sit down at 11:00 am (1000 GMT) at UN headquarters in Geneva.
UN mediator Lakhdar Brahimi spent Thursday trying to convince them to be in the same room for the start of the talks -- the biggest diplomatic effort yet to stem the bloodshed in Syria's devastating civil war.
But UN spokeswoman Alessandra Vellucci told reporters that Brahimi would instead meet with the Syrian government delegation at 11:00 am and then the opposition at 4:00 pm.
"Both meetings will be bilateral," she said.
"This process is shaping up, so there have been changes to previous declarations," Vellucci said. "We are going step by step."
Sources within the delegations told AFP the opposition had refused to sit in the same room unless the regime accepted the need for a transitional government without Assad.
Syrian Deputy Foreign Minister Faisal Moqdad told reporters the opposition was obstructing the talks
"The problem is that these people do not want to make peace, they are coming here with pre-conditions," he told reporters.
"Of course we are ready to sit in the same room. Why are we coming here then?"
Nazir al-Hakim, a member of the opposition delegation, told AFP it was only willing to negotiate on the basis of the agreement reached at the "Geneva I" peace conference in 2012, which called for the creation of a transitional government.
"We agree to negotiate on the application of Geneva I. The regime does not accept that," he said.
"We will be in the same room when there is a clear agenda for negotiations. We need guarantees that Geneva I will be discussed," Hakim said.
The regime rejects the opposition's contention that the Geneva I agreement requires Assad to go.
Signup to our newsletter and follow us on Facebook and Twitter!
Low expectations for breakthrough
Expectations are very low for a breakthrough at the Geneva II discussions, which officials have said could last up to 10 days.
But diplomats believe that simply bringing the two sides together for the first time is a mark of progress and could be an important first step.
With no one appearing ready for serious concessions, mediators will be looking for short-term deals to keep the process moving forward, including on localised ceasefires, freer humanitarian access and prisoner exchanges.
Brahimi said he "had indications" from both sides that they were willing to discuss these issues.
The opposition arrived in Switzerland with a sole aim -- toppling Assad -- while the regime says any talk of removing the Syrian leader is a "red line" it will not cross.
The start of the conference in the Swiss town of Montreux on Wednesday was marked by fiery exchanges, with Syrian Foreign Minister Walid Muallem labelling the opposition "traitors" and agents of foreign governments.
But UN leader Ban Ki-moon urged the two sides to work together, saying: "Enough is enough, the time has to come to negotiate."
Erupting after the regime cracked down on protests inspired by the Arab Spring, Syria's civil war has claimed more than 130,000 lives and forced millions from their homes.
Pitting Assad's regime, dominated by the Alawite offshoot of Shiite Islam, against largely Sunni Muslim rebels, the war has unsettled large parts of the Middle East.
Shiite Iran and its Lebanese militia ally Hezbollah have backed Assad; the mainly Sunni Arab Gulf states have supported the opposition; and the violence has often spilled over into neighbouring Lebanon and Iraq.
It took months of efforts to convince the two sides to come to the conference, with the opposition Coalition only deciding at the last minute to attend.
The debate over whether to take part exposed deep divisions within the opposition, with its biggest bloc, the Syrian National Council, quitting the coalition after the decision was taken.
Questions have been raised about whether the opposition delegation is truly representative of Assad's opponents and if it would be able to implement any deal with rebel fighters on the ground.