The UN is to start a new round of indirect talks in Geneva aimed at ending the conflict in Syria.
UN special envoy Staffan de Mistura has warned that there is an urgent need for the government and opposition to take steps towards a political transition.
But correspondents say the outlook is bleak, with fighting in Aleppo province threatening a fragile six-week truce.
Meanwhile parliamentary polls, dismissed by the opposition as a sham, are under way in government-held areas.
Russia, a staunch ally of President Bashar al-Assad, has said the vote does not go against the peace talks and is line with the constitution.