Greece is among the countries that have been invited to the Geneva II talks aimed at achieving a peace settlement in Syria.
UN Secretary-General Ban Ki-moon said that apart from the 30 countries that are already due to take part in the negotiations, he has invited another 10 additional countries to attend the Vatican, Australia, Bahrain, Belgium, Greece, Luxembourg, Mexico, the Netherlands, South Korea and Iran.
The talks will begin in Montreux, Switzerland on January 22 but the full negotiations between the Syrian government and opposition would begin in earnest on January 24 in Geneva.
Syria's political opposition said on Monday it will withdraw from international peace talks scheduled this week unless Ban retracts an invitation to Iran, President Bashar al-Assad's main backer.
Washington, however, suggested it could support Iran's participation if it explicitly declares its support for a June 2012 plan for a political transition that the United States says means Assad would have to step down.
The idea of what UN diplomats refer to as the «Geneva 2» peace conference on Syria was first proposed by Russian Foreign Minister Sergei Lavrov and U.S. Secretary of State John Kerry last spring, though it has taken nearly a year to organize.