Most of Syria's opposition groups have agreed to meet with the government next month for talks on a political settlement of their five-year civil war, in a potential breakthrough for peace negotiations.
After two days of talks sponsored by Saudi Arabia, more than 100 delegates ranging from secularist Damascus politicians tolerated by President Bashar al-Assad's regime to hardline Islamist rebels agreed to prepare for peace talks at the beginning of next month with Assad's government, the Saudi conference chairman said December 11.
"The participants are ready to negotiate...within a specific timeframe that would be agreed on with the United Nations," the disparate groups said in a statement.
But the opposition put one big condition on their engagement in talks: that "Bashar al-Assad and his aides quit power with the start of the transition period" for setting up democratic elections and governance.
The United States quickly hailed the agreement, with Secretary of State John Kerry calling it an "important step" towards finding peace in Syria.
"We welcome the positive outcome...including reaching a consensus on principles for a pluralistic and democratic Syria," Kerry said.
"While this important step forward brings us closer to starting negotiations between the Syrian parties, we recognize the difficult work ahead, and remain determined to continue toward a political settlement that brings an end to the conflict."
Most Syrian opposition groups attended the Riyadh meeting except the Islamic State group and Nusra Front, Al-Qaeda's Syrian affliate. Also excluded was the main Kurdish force controlling large parts of northern Syria.
The unanimity of the accord was marred by a protest from one powerful insurgent group, Ahrar al-Sham.
In a statement, it said it had withdrawn from the Riyadh meeting, objecting to what it said was a prominent role given to the mainly Damascus-based political opposition group, the National Coordination Body for Democratic Change, which it said was closer to Assad than to the opposition.
It also said rebel fighters had been underrepresented at the talks and their voices largely ignored, while the conference failed to "confirm the Muslim identity of our people."
Whether Ahrar al-Sham's dissent will pose a major obstacle to the peace process remains to be seen. Reuters reported that despite the group's objection, one of its delegates signed a copy of the final statement along with the other groups.
Rifts among the numerous groups fighting Assad have bedevilled Western and Gulf Arab efforts at fostering peace talks in the past. This week's Saudi effort appears to have been the most successful thus far at forging unity between the disparate players.
Abdulaziz al-Sager, a Saudi academic who chaired the Riyadh talks, said the opposition would meet government officials in the first 10 days of January, the first such talks in two years aimed at ending a bloody civil war.
The meeting will be hosted by United Nations Syrian envoy Staffan de Mistura with an eye toward moving to a transitional period of governance, he said in comments translated at a news conference.
The group statement said Assad should leave power at the start of a transitional period, and called for an all-inclusive, democratic civic state. It also committed to preserving state institutions.
The opposition also said it is willing to accept a UN-supervised cease-fire.
The Riyadh meeting called on the UN to pressure the Syrian government to make a series of confidence-building moves before peace talks start, including suspending death sentences against opponents, releasing prisoners, and lifting sieges.
Under the agreement, opposition groups will form a 30-member "supreme committee for negotiations" based in Riyadh that will act as a reference for their negotiating team, whose members the body will choose.
Participants also committed to a political system which "represents all sectors of the Syrian people," and would not discriminate on religious or sectarian grounds -- in a gesture towards minority Alawite, Christian, and Kurdish populations.
International efforts to resolve the conflict got a big boost this year after Russia entered the conflict and dire humanitarian conditions in the country spawned a massive flow of refugees that flooded into Europe.
Major powers agreed in Vienna last month to revive diplomatic efforts to end the war, calling for peace talks to start by January and elections within two years.
One major potential point of contention raised by the Riyadh agreement is its insistence that Assad and his lieutenants play no part in a political transition. Russia and Iran have insisted Assad's fate should be decided in elections, which would occur during the transition.
Some Western countries, while insisting that Assad ultimately must go, have been flexible about the timing of his departure, indicating that they could accept his staying on in an interim period.
Iran has openly criticized the talks sponsored by rival Saudi Arabia, a top financer of Syrian rebel groups. On December 10, Iranian Deputy Foreign Minister Hossein Amir-Abdollahian said some groups linked to IS were involved in the Riyadh meeting.
"Terrorist groups pretending to be moderate opponents [of the regime] and seeking to determine the future of Syria and the region will not be permitted," Abdollahian was quoted by state television as saying.
"Only the people of Syria can decide the future of their country."