As reported by Censor.NET, this was announced by Deputy Secretary-General of NATO Alexander Vershbow in an interview to TSN.
According to him, both local forces, which are called "volunteers from Russia," and regular Russian troops are acting in the Donbas. Despite the fact that Russian military have taken off their insignia and made up call signs for themselves, NATO knows for sure from intelligence and social media that a lot of Russian military are currently deployed in the eastern Ukraine.
Vershbow said that the presence of Russian military in the Donbas looks as if the Kremlin is trying to aggravate the situation even more. He listed usage of heavy weapons and the cease-fire violations by militants as a proof to that.
Deputy Secretary-General could not say whether it was a beginning of another military campaign or a pressure tactics used for influencing the political situation inside Ukraine. On NATO's standpoint, all provision of the Minsk agreement, including the cease-fire regime, should be fulfilled. Political provisions should also be implemented together with security provisions. Vershbow stressed that the process should take place simultaneously by both sides, not Ukraine first, Russia second.
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