There were reports of people being treated for symptoms including convulsions and foaming of the mouth, consistent with nerve or mixed nerve and chlorine gas exposure.
The UN Security Council will hold an emergency meeting on Monday, April 9, to discuss reports on chemical weapons attack in Syria.
"UK, France, U.S., Poland, Netherlands, Sweden, Kuwait, Peru and Cote d'Ivore have called an emergency meeting of UNSC. Meeting expected on Monday," The United Kingdom Mission to the United Nations tweeted on April 8.
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The U.S. state department said reports suggested "a potentially high number of casualties", including families in shelters.
The pro-opposition Ghouta Media Center tweeted that more than 75 people had "suffocated", while a further 1,000 people had suffered the effects of the alleged attack.
It blamed a barrel bomb allegedly dropped by a helicopter which it said contained Sarin, a toxic nerve agent.
There were reports of people being treated for symptoms including convulsions and foaming of the mouth, consistent with nerve or mixed nerve and chlorine gas exposure.
Syria's government has called the allegations of a chemical attack a "fabrication".