UN calls emergency talks after 'gas attack'

The UN Security Council is to hold emergency talks after an alleged chemical attack in Syria left dozens of civilians dead and wounded.

The United States, Britain and France on Tuesday proposed a United Nations Security Council resolution condemning the attack, which they have blamed on Assad's forces.

Diplomats said the resolution would likely be put to a vote on Wednesday.

A suspected chemical attack in rebel-held northwestern Syria killed dozens of civilians including children and left many more sick and gasping.

The attack on the town of Khan Sheikhun, in the Idlib province, killed at least 58 civilians and saw dozens suffer respiratory problems and symptoms including vomiting, fainting and foaming at the mouth, the Syrian Observatory for Human Rights monitoring group said, adding that at least 19 children and 13 women were among the dead.

The US government believes the chemical agent sarin was used in the attack, a US government source told Reuters news agency, adding it was "almost certainly" carried out by forces loyal to Syrian President Bashar al-Assad.

Syria's opposition also blamed President Bashar al-Assad's forces, saying the attack cast doubt on the future of peace talks.

The army denied any involvement in a statement blaming "terrorist groups" for using "chemical and toxic substances.

Russia's defence ministry said a Syrian air strike had hit a rebel ammunition store that included chemical weapons.

In particular, "a workshop for the production of land mines filled with poisonous substances" had been hit, it said.

It seemed to support accounts by Syrian military sources a day earlier who reported an explosion at what they called a rebel chemical weapons factory in Khan Sheikhoun.

If confirmed to be an attack, the incident would be the deadliest chemical attack in Syria since sarin gas killed hundreds of civilians in Ghouta near Damascus in August 2013. Western states said the Syrian government was responsible for that attack. Damascus blamed rebels.

The release of chemicals in a rebel-held town in Idlib province brought furious international reaction.