According to the BBC, the Russian energy firm Gazprom has told Poland and Bulgaria that it will stop supplying natural gas tothem starting Wednesday. Russia has said that "unfriendly" countries must pay for gas in rubles, and both countries have refused to do so. Poland gets 53% of its gas from Russia, and Bulgaria gets 90%, but both countries said they would be able to cope with the cutoff. The EU gets 40% of its natural gas from Russia.
The gas cutoff illustrates the importance of having a variety of energy sources, including nuclear.