U.S. Secretary of State John Kerry says he expects Syria's government and the main opposition coalition to attend a peace conference in early June.
Speaking in Stockholm Tuesday, Kerry said Russia has informed him that the Syrian government has presented names of potential negotiators.
Syrian state media quotes Information Minister Omran al-Zoubi as saying the government needs more details before making a final decision whether to attend the talks.
Kerry warns Syria that a boycott would be a "miscalculation" and drum up more support for the opposition.
Russia and the United States agreed last week to arrange peace talks despite their sharp disagreements over Syria. Russia is a long-time ally of Syrian President Basher al-Assad while the United States has been sending non-lethal aid to the rebels.
Kerry said last week that the outcome of a peace conference could influence a U.S. decision whether to arm the opposition.
French Foreign Minister Laurent Fabius has acknowledged that diplomatic efforts to bring Syria's warring parties together are "very difficult." He said the two sides have to agree on negotiators who do not have "blood on their hands" from the conflict, which has killed more than 80,000 people overt the last two years.
Russian President Vladimir Putin said it is extremely important for all parties to avoid actions that could aggravate the situation in Syria. He made the comment after talks with Israeli Prime Minister Benjamin Netanyahu Tuesday in the Russian resort of Sochi.
Netanyahu said he and Putin are trying to find ways to strengthen stability and security in the Middle East by explaining their positions to each other "directly" and "openly."