THE HAGUE, Netherlands (AP) -- U.N. experts are ready to move into Syria immediately to investigate reported chemical weapons attacks but President Bashar Assad's government still has not approved their entry, U.N. Secretary-General Ban Ki-moon said Monday.
Ban told reporters in The Hague that an advance team is already waiting on Cyprus while the U.N. negotiates "technical and legal" issues with Damascus.
All reports of chemical attacks "should be examined without delay, without conditions and without exceptions," Ban said. "The longer we wait, the harder this essential mission will be."
His comments appeared aimed at increasing the pressure on Assad's regime and ensuring that U.N. inspectors are given access to all sites of reported chemical weapons attacks in the country's bloody civil war and not just those that Assad's regime wants them to see.
Ban said it is "a matter of principle" to investigate all allegations and not just a case in which Syria alleges that the rebels used poison gas.
"I am hopeful we will be able to finish this as soon as possible, and I urge the Syrian government to be more flexible so this commission can be deployed as soon as possible," Ban said. "We are ready."
The U.N. says over 70,000 people have been killed in Syria's civil war since it began as an uprising against Assad's regime two years ago.
Syria asked the United Nations last month to investigate an alleged chemical weapons attack by the rebels on March 19 on Khan al-Assal, a village in northern Aleppo province. The rebels have blamed regime forces for the attack.
Syria is widely believed to have a large stockpile of chemical weapons, but it is one of only eight countries in the world that have not signed up to the chemical weapons convention. That means it does not have to report any chemical weapons to the Hague-based organization that monitors compliance with the treaty.
Britain and France have followed up by asking the U.N. chief to investigate allegations of chemical weapons use in two locations in Khan al-Assal and the village of Ataybah, in the vicinity of Damascus, all on March 19, as well as in Homs on Dec. 23.
The delay in getting to the scene of alleged chemical attacks will hamper investigators, said Amy Smithson, a chemical weapons expert with the Center for Nonproliferation Studies in the United States.
"It is going to make it a bigger challenge. But it doesn't mean you should throw in the towel," Smithson said in a telephone interview.
Investigators will likely go after two key sources of evidence -- environmental samples and samples taken from survivors and possibly also victims of suspected chemical attacks.
"It's a site of hostilities, so when the environment has changed that makes it that much more challenging to get a clean environmental sample," Smithson said.
Ban was speaking at the headquarters of the Organization for the Prohibition of Chemical Weapons in The Hague, which is sending a team of 15 experts to join the commission, along with World Health Organization staff.
The team is led by Ake Sellstrom, a Swedish professor who was a U.N. chemical weapons inspector in Iraq and now works at a research institute that deals with chemical incidents. Ban said he spoke to Sellstrom on Sunday night and he was now heading to join the advance party in Cyprus.
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