Political attention and research on the Russian challenge to the EU’s energy security has notably declined in the last couple of years, despite Russia maintaining its share in the EU import of oil and natural gas. This decline of interest is partly due to Russia scaling down the aggressive nature of its energy policy. Indeed, despite the protracted armed conflict with Ukraine, the transit of Russian gas through this country has not suffered any major interruptions, like the two-week long “gas war” in January 2009. To a significant degree, however, the shift in attention is caused by the fast-progressing changes in the conceptualization of EU’s energy security, in which problems pertaining to the environment and climate now claim greater priority than possible disruptions of supply. The Russian leadership remains a firm believer in the key role of hydrocarbons in world energy business as well as a cynical sceptic regarding renewable sources. The Energy Security Doctrine, approved by President Vladimir Putin on 13 May 2019, identifies international efforts to progress in “green energy” as a challenge to Russia’s oil-and-gas industry. Nevertheless, Russia’s prudent behavior in the European energy markets does not mean that the prospect of “weaponizing” gas flows has disappeared.