The Arab League has approved by a majority vote sweeping economic sanctions on Syria over its crackdown on protesters.

The Qatari foreign minister has said that other foreign powers could intervene if Arabs failed to contain the crisis.

Qatari Prime Minister and Foreign Minister Sheikh Hamad bin Jassim al-Thani has previously said Arabs wanted to avoid a repeat of what happened in Libya, where a UN Security Council resolution led to NATO air strikes.

"All the work that we are doing is to avoid this interference," he said, adding that if the international community did not see that Arabs were "serious" he could not guarantee that such action would be avoided.

The League approved sanctions that included a travel ban on top Syrian officials, freezing assets related to President Bashar al-Assad's government, halting dealings with Syria's central bank and stopping investments in Syria.

Ministers told the Arab League's economic and social council to draw up measures after Damascus ignored a deadline to let in Arab monitors and take other steps to end the government crackdown on an eight-month uprising against Assad's rule.

Hundreds of people, including civilians, soldiers and army deserters, have been killed in Syria this month - possibly the bloodiest since the unrest broke out in March inspired by uprisings which overthrew leaders in Tunisia, Egypt and Libya.

The United Nations says more than 3,500 people have been killed in total.

Turkey's Foreign Minister Ahmet Davutoglu is also in Egypt adding pressure on Damascus from its biggest neighbour.

He said Turkey was ready to act in unison with the League if Syria failed to show good intentions in halting the crackdown.