Assad's violent response to the uprising has killed more than 5,000 people, by a UN count. The Syrian authorities say 2,000 members of the security forces have also been killed.

"Today, I say again to President Assad of Syria: stop the violence, stop killing your people. The path of repression is a dead end," UN Secretary-General Ban Ki-moon told a conference in Lebanon on democratic transitions in the Arab world.

"From the very beginning of the ... revolutions, from Tunisia through Egypt and beyond, I called on leaders to listen to their people," Ban said. "Some did, and benefited. Others did not, and today they are reaping the whirlwind."

Syria's state news agency said Assad had granted an amnesty for "crimes committed in the context of the events since March 15, 2011, until January 15, 2012." The amnesty would run to the end of the month, covering army deserters and people held for having unauthorized arms or violating laws on peaceful protest.

Addounia television said Arab League monitors discussed implementing the amnesty with Damascus police on Sunday. They also visited a hospital in the coastal city of Banias.

Anti-Assad protests began in March inspired by a wave of popular anger against autocratic rulers sweeping the Arab world.

Assad has issued several amnesties since the start of protests, but opposition groups say thousands of people remain behind bars and that many have been tortured or abused.

The Avaaz campaign group said on December 22 that at least 69,000 people had been detained since the start of the uprising, of whom 32,000 had been released.

Freeing detainees was one of the terms of an Arab peace plan, which also called for an end to bloodshed, the withdrawal troops and tanks from the streets and a political dialogue.

The movement to end more than four decades of Assad family rule began with largely peaceful demonstrations, but after months of violence by the security forces, army deserters and insurgents started to fight back, prompting fears of civil war.

State media and an opposition group said at least five textile workers were killed when bomb hit their in the northern province of Idlib on Sunday. SANA