Both sides in Syrian civil war claim chemical weapons were used on them

The Syrian regime and rebels have traded accusations over the use of chemical weapons, allegations that if proven could force the West towards a more robust military intervention.

The accusations centred on an attack on the Khan al-Assal area of Aleppo in which at least 25 people died. The Syrian regime described it as a “dangerous escalation” while rebels blamed the government and claimed there had been another chemical attack in the Damascus suburb of east Ghouta.

The US, which has so far resisted military action in the two-year-old civil war, has repeatedly warned that the use of chemical weapons is a “red line”. While the regime has a large stockpile of chemical weapons, including sarin gas and nerve agents, the rebels are not known to be in possession of such agents, or the means with which to launch them.

State television showed footage of alleged victims on stretchers being given oxygen masks and drips. One doctor who was interviewed said “poisonous gas and phosphorus” had been used. A Reuters photographer said that patients had told him they smelt chlorine in the air and had seen people suffocating in the streets.

Senior rebel commander Colonel Qassim Saadeddine said regime forces had fired a scud missile carrying chemical weapons. Activists released videos of alleged victims of another attack in the outskirts of Damascus.

It is the first time Bashar al-Assad’s government has claimed that chemical weapons have been used. The British Foreign Office said the use of chemical weapons would require a “serious response” and force a reassessment of policy. The White House said it was “deeply sceptical” that chemical weapons had been used by rebels and warned the government not to use the reports as a “pretext” for attacks.