In Dublin, a solidarity demonstration will take place outside the GPO at lunchtime
Syrian opposition leaders have agreed to attend peace talks in Geneva next week.
Tuesday marks five years since the uprising began, with upwards of 400,000 people said to have died since.
The move has been welcomed by the US. However concern is being raised over continued airstrikes by the Assad regime.
Spokesman for the America Department of State John Kirby spoke to reporters earlier:
Meanwhile a demonstration in solidarity with the people of Syria will take place in Dublin this lunchtime.
Valerie Hughes of the Irish Syria Solidarity Movement explains why they've organised today's event:
According to a report by aid agency World Vision, the ongoing conflict cost €1.2 trillion.
World Vision provides food, health assistance and education in Syria and to Syrian refugees in neighbouring countries. It estimates that the war so far has cost the Syrian economy €2.5 billion.
Graham Davison is Programmes Director with World Vision Ireland and says these figures highlight the Syrian's plight: