The Arab League has called on the Syrian army to stop the killing of civilians and said it was suspending Syria from the regional body.
The League will impose economic and political sanctions on Bashar al-Assad's government and has appealed to its member states to withdraw their ambassadors from Damascus, said Qatar's Prime Minister Sheikh Hamad Bin Jassim.
He said the suspension would take effect on 16 November.
"We were criticised for taking a long time but this was out of our concern for Syria," he told reporters in Cairo. "We needed to have a majority to approve those decisions."
"We are calling all Syrian opposition parties to a meeting at the Arab League headquarters to agree a unified vision for the transitional period," Mr Jassim said.
Syria's representative to the Arab League said the decision to suspend Damascus violated the organisation's charter and showed it was "serving a Western and American agenda".
Youssef Ahmed told Syrian state television that the move to suspend Syria, which was opposed by two delegates at the Arab League ministerial meeting in Cairo, could only be taken by consensus at a summit meeting of Arab leaders.
