Syrian opposition groups rejected a compromise plan for a new transitional government worked out by world and regional powers.
U.S. Secretary of State Hillary Clinton already said she believes the plan "may fail". The original agreement by former U.N. secretary-general Kofi Annan had to be changed because Russia wanted to exclude President Bashar Assad.
The new plan does not bar Assad from participating. As many as 76 people were killed in violence across the country on Saturday alone.