Syrian government and opposition delegations are expected to discuss prisoner releases on their second day of face-to-face peace talks in Geneva.
On Saturday the talks focused on safe routes for aid convoys into besieged parts of the city of Homs.
UN mediator Lakhdar Brahimi called the discussions a "good beginning".
He said the issues being discussed were a prelude to tackling the key question of establishing a transitional government for Syria.
"We haven't achieved much but we are continuing," he told reporters after Saturday's talks.
Mr Brahimi said he was trying to build confidence by broaching humanitarian issues first.
The BBC reports that in the first meeting, the two delegations filed in through separate doors into one room in the UN Geneva Headquarters, and sat down at the same U-shaped table, but said nothing to each other.
Mr Brahimi said another two-hour meeting had taken place in the afternoon. He admitted no direct words had been exchanged but said the two sides were "talking through me to one another.
"This is what happens in civilised discussions," he said, where sides addressed each other via the chairperson.
