The U.S. and Russian foreign ministers, John Kerry and Sergei Lavrov, are meeting with their French counterpart in Paris to discuss the prospects for a Syrian peace conference.
Syrian Foreign Minister Walid al-Moallem announced on May 26 that the Damascus government was ready “in principle” to attend international talks jointly sponsored by Washington and Moscow.
However, it remained unclear whether Syria’s civilian opposition will take part.
The opposition remains divided over factional disputes and the influence of Islamists and has ruled out negotiations with President Bashar al-Assad’s government.
Iran’s involvement also remains in doubt, with France ruling out Tehran's participation.
France says Tehran is firmly in the Syrian government’s camp and has taken actions to support government forces.
Iran has rejected the charges, instead accusing Paris of interfering in Syria.
Russia, which is also a traditional ally of the Syrian regime, says it supports Iran taking part in any conference.
Despite deep differences over the conflict -- Washington has backed the opposition and called on Assad to step down -- the United States and Russia have jointly launched the initiative for possible international talks in Geneva.
No date for a conference, or its participants, has yet been agreed.
The situation has been further complicated by the recent entrance of Lebanese Shi’ite Hizballah fighters on the government’s side.
The leader of Iranian-backed Hizballah, Hassan Nasrallah, vowed that Hizballah would back the government until it achieved victory over opposition forces.
Hours after the declaration, rockets on May 26 hit a Hizballah-controlled area of the Lebanese capital, Beirut, renewing concerns about a spillover of the Syrian conflict to neighboring countries.
Hizballah fighters have been engaged in combat against rebel forces for the past week in the border town of Qusair.
Meanwhile, European Union foreign ministers are due to meet to discuss lifting an embargo to help Syria’s opposition obtain weapons.
France and Britain support easing the embargo, but other EU states are reluctant to take such a step. The embargo is due to expire at the end of May.
Civilian opposition factions held talks in Istanbul over the past four days but failed to reach any unified commitment to take part in a peace conference.
Syrian National Coalition representative Louay Safi told reporters that the opposition continues to insist that Assad agree to leave power as part of any political process.
He also expressed alarm over Hizballah becoming a factor in the conflict. The opposition has accused Hizballah of fighting as a proxy for Iran.
The United Nations has estimated that at least 80,000 people have been killed in the past two years of the Syrian conflict.
With reporting by Reuters, AFP, and dpa