The head of the Arab League monitoring mission in Syria says that violence has escalated significantly over the last three days.
Dozens of deaths were reported by human rights activists on Friday with the restive cities of Homs and Hama once again at the centre of the bloodshed.
UNICEF says that during the 10 month revolt against President Assad, at least 384 children have been killed.
The Arab League wants Assad to quit as part of a transition plan for which it is seeking UN support. The UN Security Council was due to discuss a new Western-Arab draft resolution. But Russia blocked a previous Western draft and has signalled it could use its veto again.