The head of the United Nations observer force in Syria has arrived there to take charge of the first deployment of monitors.
A ceasefire between rebels and government troops took effect on 12 April and Major General Robert Mood of Norway and 15 unarmed military observers already there, have the job of monitoring it.
Major General Mood said bringing peace to the country will require a collaborative effort from the government, rebels and civilians.
''Ten unarmed observers, 30 unarmed observers, 300, even 1000 unarmed observers cannot solve all the problems,'' he said on Sunday.
"I call on everyone to help us and cooperate with us in this very challenging task ahead."