As reported by Censor.NET, this was said by Chargé d'Affaires of the U.S. Mission to OSCE Kate M. Byrnes as she delivered her speech to the OSCE Permanent Council on Feb. 9, 2017.
According to her, there is clear evidence of a military buildup by combined Russian-separatist forces in the area in advance of the offensive.
"A week before the assault began, the SMM observed trucks which were carrying boxes of ammunition assessed as matching the shape and size of MLRS rockets in the separatist held town of Khrustalnyi. Two days before the assault began, an SMM UAV spotted 45 military-style trucks 500 meters from a railway station in separatist-held Amvrosiivka, which lies only 15 kilometers from the Russian border," the diplomat said.
"Separatists harassed the SMM monitors and delayed them from leaving the site. That same day, SMM monitors were denied access at another separatist-held town, Markyne, less than 5 kilometers from the Russian border. Satellite images show not less than six artillery positions on separatist-controlled territory within striking distance of Avdiyivka.
"Combined Russian-separatist forces have been expanding their positions in Avdiyivka in the past six months - including into areas on the Ukrainian side of the line of contact.
This is a fight for which Russia and the separatists had prepared. As soon as the fighting started, combined Russian-separatist forces blocked the SMM's access to Yasynuvata - and kept the restrictions in place for the next three days," Byrnes said.
She called on Russia to end its aggression against Ukraine: "Our sanctions remain in place. We again call on Russia to comply fully with its commitments under the Minsk agreements. Proscribed weapons must be withdrawn, a comprehensive ceasefire must be sustained, and effective border monitoring must be established. We again call on Russia to observe the Helsinki Final Act, in which all participating States agreed that one another's frontiers are inviolable and that they will respect the territorial integrity of each participating State."
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