Bulgaria says it's working to find alternative sources of gas.
Russia's suspending gas supplies to Poland and Bulgaria from today, escalating its row with Western nations following its invasion of Ukraine.
Both nations have refused Moscow's demand to pay for the energy in Russian currency.
President Putin brought-in the rule - a move aimed at propping-up the rouble - in response to Western sanctions over the war in Ukraine.
Poland insists it has enough reserves, while Bulgaria says it's working to find alternative sources of gas.
In the meantime the conflict continues.
Russian political analyst Dmitry Babich thinks Vladimir Putin's latest strategy will be to target highly-trained Ukrainian troops, capable of deploying heavy weapons.
Lisa Ryan Professor of Energy Economics at UCD says while there could be wider implications for Europe, it will hurt Russia more.