Syrian gunships pound rebels and troops clash with insurgents in Aleppo as world powers voice calls for "maximum pressure" to prevent a massacre.
President Bashar al-Assad says Syria is in a state of war, ordering his Cabinet to crush the revolt even as fierce fighting continues near Damascus.
Clashes between regime forces and rebels in Syria has killed 23 Syrian soldiers and wounded dozens as the EU slaps fresh sanctions on the regime.
UN-Arab League envoy Kofi Annan says his peace plan could be the last bid to avoid war in Syria, where a truce has failed to end months of bloodshed.
Syrian troops have killed four students and arrested some 200 after storming an anti-regime protest at Aleppo University, in the north of the country.
Rebels have killed more than 20 troops in the Syrian army's deadliest day of a ceasefire deal even as UN observers say they have a "calming" impact.
Violence has erupted in two Syrian provinces with reports of 10 civilians dead in an army mortar attack and 12 soldiers killed in clashes with rebels.
Syria has told Arab League envoy Kofi Annan that it has begun pulling troops in line with a peace plan accepted by President Bashar al-Assad.
Activists accuse Syrian troops of shelling two cities in an effort to weaken forces fighting Bashar al-Assad's government before a ceasefire deadline.
South Africa has condemned the escalating violence in Syria and has urged all parties involved to seek a peaceful solution to the ongoing conflict.
Rebels are fighting security forces in Damascus in the most violent gun battles the Syrian capital has seen since the start of the year-long uprising.
Syria has been hit by the weekend's third car bomb as UN teams ready for a government-led humanitarian mission and to work on an observer operation.
Rights activists have reported the death of several Syrian soldiers after being ambushed by Syrian army defectors.
Syrian troops have pressed a relentless assault on the flashpoint Syrian city of Homs for a fifth straight day, killing dozens more civilians.
Syria has rejected the Arab League's plan to end the country's conflict, saying the call for a unity government is a violation of Syria's sovereignty.
The Arab League has met for talks to extend its observer mission to Syria, with Riyadh 'pulling its observers' as Damascus has not kept its promises.
Fierce fighting has continued in Syria shortly before officials arrive to prepare for an Arab League effort to end nine months of bloodshed.
The Arab League expects Syria to agree soon to allow observers in to monitor and mediate the protection of civilians while peace talks get under way.
Activists have called for a general strike to increase pressure on Syria's president's regime as fears grow of an 'invasion' of protest hub, Homs.
Turkey has told Syria's President Bashar al-Assad to step down for the sake of his people, tightening regional pressure on Damascus.