Hoping to build on the momentum of a US-Russia accord to destroy Syria's chemical arsenal by mid-2014, Lakhdar Brahimi has been criss-crossing the region to rally support for a new international conference aimed at ending the Syria conflict.
He began talks with Russian deputy foreign ministers Gennady Gatilov and Mikhail Bogdanov and US Under Secretary of State for Political Affairs Wendy Sherman Tuesday morning at the UN's European headquarters.
Representatives of the three other permanent members of the UN Security Council — China, France and Britain — will join the meeting later Tuesday.
A UN announcement that Syria's neighbours, Iraq, Jordan, Lebanon and Turkey, as well as the UN and the Arab League would take part in Tuesday's talks was seen as an indication preparations for the conference, dubbed Geneva II, were finally picking up speed.
But it remains unclear whether the parties will manage to agree on who should participate and whether they can find a way to end the spiralling 31-month conflict that has killed more than 120,000 people and forced millions more to flee their homes.
Syria's ever more splintered opposition has refused to attend peace talks unless Assad's resignation is put up for discussion — a demand rejected by Damascus.
Late Monday, Syria's information minister stressed that the regime would not take part in the proposed conference if the aim is for the Syrian president to give up power.
"We will not go to Geneva to hand over power as desired by (Saudi Foreign Minister Prince Saud) al-Faisal and certain opponents abroad," said Omran al-Zohbi in comments carried by the official SANA news agency.
Some opposition rebel groups have meanwhile warned that anyone who participates in the conference will be considered traitors.
Complicating the issue further, Russian Foreign Minister Sergei Lavrov reiterated on Tuesday that Moscow wants Iran to have a seat at the Geneva II table, stressing that "all those who affect the situation must be invited to the conference."
Syrian opposition leader Ahmad Jarba has earlier rejected the rebels' participation if Iran is asked to attend.
Brahimi has warned that "if the opposition does not participate there will be no Geneva conference."
The veteran Algerian diplomat said after a meeting with Assad in Damascus last week that the Syrian government had agreed to take part in the talks while the opposition was "trying to find a way to be represented".
"We hope it will take place in the next few weeks, not next year," he said.
Striving for a 'definitive date'
The conference is meant to follow up on a meeting last year that produced a transition plan for the war-ravaged country which was never implemented.
It was initially planned for June, but has been repeatedly delayed amid stark disagreement over who should have a seat at the table.
Word in diplomatic circles has long been that the conference would be held on November 23rd, although the United Nations has never confirmed that date.
Brahimi said late last week that those taking part in Tuesday's meeting would strive to "agree on a definitive date, which will be announced in the coming days."
Arab League foreign ministers meanwhile gathered in Cairo on Sunday to push the Syrian opposition to attend Geneva II.
At the start of the Cairo meeting, Ahmed Jarba, who heads the main umbrella opposition National Coalition, emphasized the group's commitment to attending Geneva II only as a united front and reiterated its unequivocal demand for a ceasefire during the talks.
The coalition has said it plans to meet in Istanbul on Saturday to decide whether to attend the peace talks, but the Syrian National Council, a key member of the bloc, has threatened to quit if it does so.