Artillery systems are reportedly being loaded onto trains.
Russia says some of its troops are moving away from the border with Ukraine after they finished exercises in the area.
Video has emerged showing tanks and artillery systems being loaded on to a train.
The United States and the UK have been among the countries which have been warning that the Kremlin could be preparing to invade.
A spokesperson from Russia's foreign ministry says it shows the "Western war propaganda failed."
Jean Monnet Professor of European Integration and Director of the Maynooth Centre for European and Eurasian Studies, Maynooth University spoke with Clem Ryan about the rising tensions on Tuesday Morning's Kildare Today:

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