Since a resumption of peace negotiations last year, there have been multiple rounds brokered by the UN between representatives of Syrian rebels and the government of President Bashar al-Assad, resulting in scant progress.
The initiative was proposed by Russia, President Bashar al-Assad’s most powerful ally, with the support of Turkey and Iran, Assad’s other major ally.
Capturing all of Aleppo would be a major victory for Syrian President Bashar al-Assad after five and a half years of fighting that has killed hundreds of thousands of people and displaced 11 million others.
The assault began last Tuesday after a weeks-long pause in air strikes and shelling inside east Aleppo.
The intense bombardment of east Aleppo have created a dire humanitarian crisis, aggravated by frequent air strikes on hospitals and polluted water bodies.
There have been night-time clashes as each day of the ceasefire has ended, but Saturday saw much fiercer fighting plus the first air strikes.
Rebels have been trying to break through a thin strip of government-controlled territory to reconnect insurgent areas in western Syria with their encircled sector of eastern Aleppo, in effect breaking a government siege begun last month.
A spokesman for the Syria Civil Defence said 33 people, mostly women and children, were affected by the gas, which they suspect was chlorine, in Saraqeb, in rebel-held Idlib province.
The lawsuit alleges that the attack on Colvin was part of a plan orchestrated at the highest levels of the Syrian government to silence local and international media “as part of its effort to crush political opposition”.