Pro-Russian separatists announced 1,200 troops and 150 vehicles including tanks trained in Russia will join their increasingly desperate fight against the Ukrainian military. Separatist leader Alexander Zakharchenko, who made the announcement in a video, did not specify the origins of the troops or weapons.

“The following reserves have been gathered: 150 armored vehicles, of which about 30 are tanks and rest are BMP and BTRs [armored personnel vehicles] and 1,200 military personnel … who underwent training for four months in the Russian Federation. They were brought into action at the most crucial moment,” Zakharchenko said in the video posted by a separatist media outlet to YouTube.

Moscow has categorically denied it is supplying any sort of military aid to separatists. On Friday, Ukrainian president Petro Poroshenko said artillery destroyed a column of Russian military vehicles in Ukrainian territory, but has yet to release hard evidence of the column’s presence in Ukraine, only saying via a spokesman that it was along “a traditional route of movement of armored convoys to the territory of Ukraine.”

The announcement of reinforcements for separatists comes as Russian and Ukrainian authorities negotiate over the fate of a 270 tractor-trailer strong Russian aid mission meant to relieve affected civilians in eastern Ukraine. The convoy sits on the Russian side of the border.

The semi-official Russian news agency ITAR-Tass said Saturday Ukraine has now “recognized” the aid mission as a bona fide relief mission and said the International Committee of the Red Cross will handle the transfer of aid from Russian to Ukrainian territory. Earlier agreements reported by ITAR-Tass have fallen apart.

Ukrainian forces have made gains in recent weeks and now have the separatist strongholds of Luhansk and Donetsk are nearly surrounded. Thousands of Ukrainians have fled the cities, many for Russia. Government shelling has devastated the region and the resulting humanitarian crisis prompted Russia to undertake the unilateral aid mission.

Reporters from the Telegraph and the Guardian tweeted photos earlier in the week of Russian military equipment staged near the humanitarian convoy and appearing to cross the Ukrainian border.