Russia, through its foreign policy wing, Gazprom, has changed its position on penalties imposed against Ukraine for not purchasing the contractual amount of gas. Now it will impose the penalties according to Kommersant Ukraina (sorry, no link). There is nothing wrong with this based on contractual law - except for the glaring fact Gazprom and Russian Prime Minister Vladimir Putin had said in March that Russia would not demand penalties connected to Ukraine’s import shortages.
The fact that Putin and Russian government are untrustworthy and, basically, liars, is secondary to the use of the oil/gas weapon to recreate the Soviet Union. But Russian proclivity for outright lies should be noted.