This was announced by Chargé d'Affaires to the OSCE Permanent Council in Vienna Kate Byrnes, Censor.NET reports.
"We are deeply concerned about information with regard to the presence of Russian military equipment and personnel in separatist-held areas," the U.S. official said.
She recalled that the OSCE Special Monitoring Mission to Ukraine's Feb. 8 weekly report noted 170 weapons in violation of withdrawal lines.
"The close proximity of so many heavy weapons keeps the risk of escalation dangerously high," she said.
Referring to a previous statement by the EU, the U.S. representative stressed that the Russians "deny their responsibility, distort the facts and hinder efforts to resolve the conflict." Unfortunately, according to her, it will be difficult for Ukrainian forces to withdraw their weapons when combined Russian-separatist forces continue to advance, digging into new positions in Sokilnyky and Stanytsia Luhanska.
"Fighting in one area can quickly ignite clashes elsewhere along the line of contact," the diplomat noted. She stressed that both sides must uphold their commitments to withdraw forces from disengagement areas and hold their fire.
"A renewed commitment to a full and lasting cease-fire is urgently needed to protect civilians and critical infrastructure," Byrnes added.
As reported earlier, the OSCE recorded 94 explosions in the Donbas on Feb. 15.
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