Reuters reports: Syria’s fractious opposition scrambled to agree a new leadership on Friday in a bid to present a coherent front at peace talks which the United States and Russia are convening to seek an end to more than two years of civil war.

A major assault by President Bashar al-Assad’s forces on a rebel held town over the past week is shaping into a pivotal battle. It has drawn in fighters from Assad’s Lebanese allies Hezbollah, justifying fears that a war that has killed 80,000 people would cross borders at the heart of the Middle East.

Washington and Moscow have been compelled to revive diplomacy by developments in recent months, which include new reports of atrocities, accusations chemical weapons were used and the rise of al Qaeda-linked fighters among rebels.