Our article we take a close look at the security of supply risks generated by the recurring political crisis between the Ukraine and Russia. If the delivery of gas is suspended or a trade ban is imposed, the countries of Central and Eastern Europe will be deprived of substantial volumes of Russian natural gas import. Using modelling tools we assess the price increase that would be elicited by substituting the lost sources of the region, and we also inspect the level of consumption restrictions needed to offset the missing sources of import. In our analysis we examine the impacts of different scenarios of import loss with respect to their level, duration and timing.