Russian dead 'being removed from Ukraine' Moscow has denied sending regular troops or military vehicles into the conflict zone although it admits that Russian volunteers, including servicemen who are "on holiday," are taking part in the fighting. Pro-Russian rebels who have been fighting Kiev's rule in eastern Ukraine since April have boasted of thousands of fighters crossing from Russia in order to support them. The separatists say their weapons are trophies seized from Ukrainian forces. Last month, however, reporters noted T-72BM tanks in the conflict zone, a type used exclusively by the Russian army, and Philip Breedlove, Nato's supreme commander in Europe, said on Wednesday that the alliance had observed "multiple columns" of Russian tanks, artillery and combat troops entering Ukraine in the previous two days. Ukraine says it is redeploying its troops in anticipation of a Russia-backed rebel offensive. The rebels currently control what they call the Donetsk and Luhansk People's Republics, which are only part of the Ukrainian regions of the same name, but they have expressed a wish to expand "Novorossiya" - a term used by the Kremlin to describe areas it believes are historically Russian. Markiyan Lubkivsky, an adviser to the head of Ukraine's Security Service (SBU) said the army was "in a state of enhanced readiness." "Today we see and document a build-up in Russia's military presence in the temporarily occupied territories, troops are being redeployed, and positions are being fortified," he told a Ukrainian television programme on Wednesday evening. There are all symptoms that Russia ... is planning or preparing for active hostilities. Russia once again denied any involvement of its troops or hardware in the conflict on Thursday. Alexander Lukashevich, a foreign ministry spokesman, told a briefing in Moscow: "I tell you completely openly and officially that there are no military movements across the border and moreover none of our military personnel have been or are present on the territory of southeast Ukraine." The crisis in Ukraine is expected to be a major point of discussion for world leaders on the sidelines the G20 economic summit in Brisbane, Australia, beginning on Friday. Earlier this week, David Cameron, the Prime Minister, warned that Russia's actions in Ukraine "pose a grave danger to the rest of Europe."