Diplomats were gathering Wednesday in the Swiss resort city of Montreaux for the launch of talks aimed at ending the nearly three-year-old Syrian conflict, dpa reported.
US Secretary of State John Kerry, Russian Foreign Minister Sergi Lavrov and UN chief Ban Ki-moon were among those expected to address delegates from more than 30 countries at the opening of the so-called Geneva 2 conference - the latest bid by the international community to push Damascus and the opposition to reach a political solution.
The head of the Syrian government delegation, Foreign Minister Walid al-Moallem, and lead Syrian opposition delegate Ahmed al-Jarba, were also expected to address the opening session.
During the talks, which are due to continue in Geneva later this week, the two sides are set to hold face-to-face talks over a potential political transition and the formation of a unity government.
The talks seek to build on an agreement reached at a previous international meeting held in Geneva in 2012. The pact fell apart after the Syrian government and rebels failed to adhere to a ceasefire.
The Montreaux talks were placed in jeopardy less than 48 hours before their scheduled opening, when the opposition threatened to withdraw from the summit over the United Nations' invitation to Iran - a key ally of Syrian President Bashar al-Assad.
The Syrian opposition accuses Iran of sending military support and fighters to combat rebel forces.
Under pressure from the opposition and the United States, Ban eventually revoked Iran's invitation.
The Syrian uprising started in March 2011 with peaceful demonstrations against the regime, but quickly descended into a civil war that has claimed 130,000 lives, according to the pro-opposition watchdog group, the Syrian Observatory for Human Rights.
The UN earlier this month said it had stopped counting the dead, citing an inability to access conflict zones. In July, it put the toll at 100,000.
More than 2.4 million Syrians have fled their country since the civil war began, with more than 6.5 million displaced inside its borders, UN agencies have said.