"A credible and comprehensive inquiry requires full access to the sites where chemical weapons are alleged to have been used. I again urge the Syrian authorities to allow the investigation to proceed without delay and without any conditions," Ban said before meeting with the head of the investigation, Ake Sellstrom, at U.N. Headquarters in New York.
Sellstrom, a Swedish scientist, was appointed to lead the fact-finding mission, named following a formal request from the Syrian government. The initial focus of the probe will be an incident involving the alleged use of chemical weapons in Kfar Dael region in Khan al-Asal area in Aleppo governate.
The fact-finding team has been on stand-by and is ready to deploy within 24- to 48 hours. An advance team is positioned in Cyprus, the United Nations said in a release.
"This is a crucial moment in our efforts to get the team on the ground to carry out its important task," Ban said. "I take seriously the recent intelligence report of the United States about the use of chemical weapons in Syria. On-site activities are essential if the United Nations is to be able to establish the facts and clear up all the doubts surrounding this issue."
Ban said Sellstrom and his colleagues have been gathering and analyzing available information while waiting for consent to enter Syria.
Noting Monday was the annual Day of Remembrance for the Victims of Chemical Warfare, Ban said, "As we address these allegations, I encourage all involved to uphold their responsibilities in enabling us to properly police these heinous weapons of massive destruction."
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