BEIRUT: The head of the rebel Free Syrian Army called on Thursday for the Arab League to withdraw its observers from Syria, qualifying the bloc's monitoring mission a failure.

"We hope they will announce that their mission was a failure and that they will be withdrawn," Colonel Riyadh al-Asaad, who is based in Turkey, told AFP in a telephone interview.

"We call on the Arab League to step aside and let the United Nations take over responsibility as it is more apt to find solutions," he added.

Arab League ministers are to discuss the mission at a weekend meeting in Egypt.

Colonel Asaad said his group did not wish for the observers to be sent back to Damascus after that meeting.

"We don't want them back in Syria," he said.

The observers have been in Syria since December 26 trying to assess the Assad regime's implementation of a peace agreement aimed at ending a fierce crackdown against a 10-month popular revolt.

The mission has come in for scathing criticism from Syrian democracy activists who denounced it as "unprofessional".