The UN Security Council said that it was necessary to clarify an alleged chemical weapons attack in Damascus suburbs on Wednesday but stopped short of demanding a probe by UN investigators currently in Syria.
"There is a strong concern among council members about the allegations and a general sense that there must be clarity on what happened and the situation must be followed closely," Argentina's UN ambassador, Maria Cristina Perceval, told reporters after a closed-door emergency meeting of the council.
The United States, Britain and France are among around 35 countries that called for chief UN investigator Ake Sellstrom, whose team is currently in Syria, to investigate the incident as soon as possible.
The White House expressed alarm on Wednesday about reports that Syrian government forces used sarin in an attack on civilians.
"The United States is deeply concerned by reports that hundreds of Syrian civilians have been killed in an attack by Syrian government forces, including by the use of chemical weapons, near Damascus earlier today," White House spokesman Josh Earnest said in a statement.
"We are formally requesting that the UN urgently investigate this new allegation. The UN investigative team, which is currently in Syria, is prepared to do so, and that is consistent with its purpose and mandate."
The UN Security Council called an emergency meeting on Wednesday at 3:00 P.M. EDT to discuss the attack, which the Syrian opposition says has killed as many as 1,300 people.
A White House spokesman said Wednesday that the U.S. will consult with its partners on the Security Council about reports of chemical weapons use in Syria.
Turkey's foreign minister said it was clear from television footage that chemical weapons, and telephoned UN chief Ban Ki-moon to urge an immediate investigation.
"Use of chemical weapons in Syria is evident from the footage coming from there," Turkish Foreign Minister Ahmet Davutoglu said in an interview on Kanal 24 television. "We have called for an immediate investigation by the UN teams." The foreign ministry said in a statement Davutoglu had called Ban to urge the Security Council to "carry out its responsibilities."
The European Union also called for a "thorough and immediate" investigation of an alleged chemical attack in after Syrian rebels said in a gas attack and shelling by President Bashar Assad's forces.
"We have seen with grave concern the reports of the possible use of chemical weapons by the Syrian regime. Such accusations should be immediately and thoroughly investigated," a spokesman for EU foreign policy chief Catherine Ashton said.
"The EU reiterates that any use of chemical weapons, by any side in Syria, would be totally unacceptable."
The Russian foreign ministry also called for what it deemed as a 'fair and professional' investigation of the Syrian chemical attack. However it added that evidence suggests reports of the attack could be "a provocation."
Britain and France will send a letter to UN Secretary-General Ban Ki-moon on Wednesday to officially request a UN investigation into an alleged gas attack in Syria, a UN diplomat said on condition of anonymity.
Western and regional countries have publicly called for UN chemical weapons investigators, who arrived in Damascus three days ago to look into previous allegations of such attacks, to be dispatched to the scene of what may be one of the deadliest incidents of Syria's two-year-old civil war.
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