Arab League foreign ministers on Sunday approved unprecedented sanctions against Syria, after Damascus failed to accept its plan to send monitors in response to a deadly crackdown on the anti-government uprising.

Following the meeting in Cairo, Qatari Foreign Minister Hamad bin Jassim bin Jaber al-Thani said that 19 of the 22 Arab League members voted to impose the sanctions. Iraq and Lebanon abstained. He said the vote will have its desired effect, even if the sanctions are never applied, as long as Syria agrees to stop targeting civilians.

The measures include a freeze on the assets on Syrian leaders in Arab states, a halt to dealings with Syria's central bank, a travel ban on top Syrian officials, and an end to Arab investments and trade with Damascus.

The Arab League head Nabil al-Arabi said that extra care will be taken to make sure that the new economic sanctions do not hurt the Syrian people or neighboring states.

The foreign ministers agreed to meet again on Saturday to review the effects of the sanctions and whether they need to be extended.

The sanctions approval is a blow for Syria, which has long prided itself as a bastion of Arab nationalism. Sunday's vote in Cairo also marks the first time in the league's 66-year history that it has imposed punitive economic and political sanctions on any of its members.

The Associated Press says Syria protested the Arab League's vote to impose sanctions, calling it a “betrayal,” while hundreds of Syrians gathered in a main square in the capital, Damascus, to condemn the move.

The measure adds to the pressure on the Syrian economy that U.S. and European Union sanctions have had on exports of Syrian oil and other products.

Arab officials proposed the sanctions after Syria refused to accept a Friday deadline they set to allow league observers into the country to monitor the government's response to the uprising. Syria instead asked the league for clarifications of the observers' mission.

Rights groups say Syrian forces killed at least 23 people across the country on Sunday.

There was no independent confirmation of the casualties because Syria bars most foreign journalists from operating in the country.

Syrian army defectors known as the Free Syrian Army have carried out increasingly deadly attacks on government forces in recent weeks, militarizing what had previously been a largely peaceful movement calling for an end to President Bashar al-Assad's 11-year autocratic rule.

The United Nations says more than 3,500 people have been killed since March in connection with the uprising.