UN mission is "uniquely capable" of establishing the evidence whether chemcial weapons were used in Syira, spokesperson for Secretary-General Ban Ki-moon reiterated on Sunday. 

UN Secretary-General Ban Ki-moon (file photo). [M. Garten/UN Photo]

The spokesperson Martin Nesirky stressed that UN mission is "uniquely capable of establishing, in an impartial and credible manner, the facts of any use of chemical weapons based directly on evidence collected on the ground."

US Secretary of State John Kerry claimed in all five Sunday talk shows on Sunday that the U.S. has evidence that toxic nerve agent Sarin was used on Aug. 21 in Syria.

An unclassified U.S. intelligence report released by the White House last Friday showed at least 1,429 Syrians, including 426 children, were killed in the sarin gas attack on that day.

"We have signatures of Sarin in hair and blood samples, so the case is growing stronger by the day," said Kerry.

Samples collected by the United Nations chemical weapons inspection team in Syria will begin to be transferred to laboratories tomorrow, said Ban's spokesperson.

"The whole process will be done strictly adhering to the highest established standards of verification recognized by the Organization for the Prohibition of Chemical Weapons [OPCW]," spokesperson Martin Nesirky told reporters in New York following a telephone call between Mr. Ban and Dr. ?ke Sellstr?m, the head of the inspection team.

Mr. Ban asked Mr. Sellstr?m to expedite the mission's analysis of the samples and information it had obtained "without jeopardizing the scientific timelines required for accurate analysis and to report the results to him as soon as possible," Nesirky said, adding that they had discussed ways to further accelerate the analysis.

Two Syrian Government officials have been observing the process, as per Mr. Ban's guidelines for the procedure, and in strictly in adherence with the established standards for verification set up by the OPCW.

Once analysis of the samples is completed, a report will be given to Mr. Ban who will share the results with all Member States, and the Security Council.

Mr. Ban has been in close contact with the five permanent members - China, France, Russia, the United Kingdom and the United States. He spoke earlier Sunday with the Foreign Minister of France, Laurent Fabius.

Mr. Ban is due to brief the 10 non-permanent members of the Security Council on the latest developments "in days to come, possibly Tuesday", his spokesperson said.