U.N. Secretary-General Ban Ki-moon says U.N. personnel will begin inspecting the site of a major suspected chemical attack near Damascus on Monday.
In a statement released by his spokesman on Sunday, Mr. Ban said the Syrian government agreed to "provide the necessary cooperation" for the U.N. team to investigate the August 21st incident.
Mr. Ban said that cooperation includes ceasing hostilities in the area of the attack in the rebel-held Damascus suburb of Ghouta.
In a separate statement, the Syrian government pledged to work with visiting U.N. disarmament envoy Angela Kane to set a date for the inspectors to travel to the district.
The inspectors led by Swedish scientist Ake Sellstrom have been in Damascus since Sunday to investigate earlier allegations of chemical attacks in the Syrian conflict.
Western powers had called on the Syrian government to give the U.N. team immediate access to the scene of Wednesday's incident, fearing any delay would enable evidence of a chemical attack to degrade or be removed.
A senior Obama administration official told Western news agencies on Sunday there is "very little doubt" that the Syrian government used a chemical weapon against civilians in Ghouta.
The official said the U.S. intelligence community and its international partners reached the assessment based on "the reported number of victims, reported symptoms of those who were killed or injured, witness accounts, and other facts gathered by open sources."
Syrian rebels and activists have said the attack killed hundreds of civilians and released footage to back up their claim, showing scores of bodies and patients writhing in agony, all with no visible wounds.
The government of Syrian President Bashar al-Assad has denied the allegations and accused rebels of using chemical weapons to try to trigger foreign intervention in the civil war.
Syrian state news agency SANA said some soldiers suffocated when "armed terrorists" staged a chemical attack in the Joubar suburb of Damascus on Saturday.
U.S. Defense Secretary Chuck Hagel said U.S. forces are prepared to take action against Syria, if President Barack Obama approves it. Speaking on a visit to Malaysia Sunday, he said Washington and its allies were still assessing how to respond.
Mr. Obama met with top U.S. military and national security advisors on Saturday to consider his options.
The office of French President Francois Hollande said he and British Prime Minister David Cameron have agreed to hold talks soon on how to respond to what the French leader called the Syrian government's "intolerable act."
It also quoted Mr. Hollande as saying the suspected chemical attack will not go "unpunished."
Israeli President Shimon Peres told visiting French Foreign Minister Lauren Fabius that the "the time has come for a joint effort to remove
all the chemical weapons" from neighboring Syria.
Israeli Prime Minister Benjamin Netanyahu suggested that he may take action against Israel's longtime enemy, telling a Cabinet meeting that "our finger is responsible, and when needed it is also on the trigger."
He said the Ghouta attack demonstrates that what he called the "world's most dangerous regimes" must not be allowed to posses the "world's most dangerous weapons."
Syria and its allies warned against any U.S.-led military strikes.
In an interview broadcast Saturday, Syrian Information Minister Omran Zoabi told Lebanon-based al-Mayadeen television that U.S. military intervention will create a very serious fallout and a "fire that will inflame the Middle East."
The head of the Russian parliament's International Affairs Committee posted a message on Twitter saying President Obama risks becoming a "clone" of his predecessor George W. Bush. Alexei Pushkov said Mr. Obama is moving toward what he called an illegitimate war in Syria in the same way that Mr. Bush did with Iraq.
Iran's Fars news agency also quoted the Iranian miltiary's deputy chief of staff Massoud Jazayeri as saying "any crossing of Syria's red line will have severe consequences for the White House."