US Secretary of State John Kerry on today spearheads a bid to drag Syria's opposition forces into peace talks with President Bashar al-Assad's regime.
At a Paris meeting that represents a critical juncture for international efforts to end a bloody conflict that has claimed more than 130,000 lives, Kerry and ministers from 10 other countries in the "Friends of Syria" grouping will seek to persuade the opposition National Coalition to attend talks due to start later this month in Switzerland.
The Coalition is profoundly divided over the issue: its main component, the Syrian National Council has long maintained that it will not enter peace talks without clear assurances that Assad will have no role in the transitional government the talks will aim to establish.
At talks in Istanbul last week, the different factions were unable to agree on terms for their attendance at the so-called Geneva II talks that are scheduled to get under way in Montreux on January 22.
Coalition leader Ahmad Jarba will be in Paris today and senior diplomats at the US State Department and in France have voiced cautious optimism that he will bow to intense pressure to ensure the rebels hold what would be the first direct talks with Assad's regime since the conflict erupted in March 2011.
"There are people all around the world doing their best to get them there and get them there with a unified position," said a senior US official involved in preparing the talks.
He described himself as "reasonably confident" that the opposition will accept that joining peace talks is the best option they have against a background of military stalemate and mounting combat fatigue in the nearly three-year-old civil war.
"I think in the final analysis they won't want to miss that opportunity, because frankly there's no other game, really," the official, speaking on condition of anonymity, told reporters.
A French diplomat added: "We think it is important that they decide to attend, even if it is only to show that you have an opposition willing to agree a process of transition on one side and, on the other, a regime that might be willing to put people on the plane to Geneva but not to negotiate a political solution."
Officials acknowledge however that advances by Syrian forces in recent days have made it harder for the opposition to contemplate sitting down with representatives of the Assad regime.
Government troops yesterday seized a previously rebel-held town in the north of the country and pushed toward part of Aleppo, the main city in northern Syria.
Observers of the conflict believe the government advances are due to opposition forces having become preoccupied with fighting a jihadist group, the Islamic State of Iraq and the Levant, with which they were previously allied.
