The Arab League has voted to suspend Syria and impose sanctions against its failure to end a government crackdown on protesters.
It asked member states to withdraw their ambassadors from Damascus and urged the government there to end violence against protesters.
Eighteen Arab League members voted at the meeting in Cairo to suspend Syria. Syria, Lebanon and Yemen voted against and Iraq abstained.
Syria has ignored proposals from the Arab League which envisaged the start of dialogue with the opposition.
The proposals which were accepted by the government of President Bashar al-Assad, include the release of prisoners, the withdrawal of security forces from the streets and talks between the government and opposition.
But the killing has continued, with the city of Homs reportedly bearing the brunt. Twelve died on Saturday and 13 on Friday. There were also reports of mass arrests after Friday prayers.
The UN says more than 3500 people have died in the protests since March.
Qatari Prime Minister Sheikh Hamad Bin Jassim said on Saturday the suspension would take effect on Wednesday, adding that talks would be held with Syrian opposition groups in three days.