The concept of “strategic autonomy” embeds the political idea of “independence” and the legal notion of “sovereignty”. As the EU largely depends for energy on foreign resources, particularly from autocratic regimes, difficult governance situations, notably wars, can deeply disrupt the Union’s energy supply. Specifically, war in Ukraine has been convincingly explained as an affirmation of the opposed development of Russia’s “sphere of influence”, whereby energy supply is used as a “weapon” to create dependency across sovereign State borders. Whereas scholars have advanced a dichotomy for the EU and its Member States to escape Russia’s sphere of influence, either diversifying energy sources or accelerating the green transition, it is argued in this paper that the two approaches should be considered complementary rather than alternative. It is therefore suggested that, at least in the short term, the EU and its Member States should seek to diversify their energy sources, whilst at the same time trying to accelerate the green transition under the Green Deal as a longer-term strategy. As the EU and its Member States should qualify as “non-belligerent” vis-à-vis Russia, necessity seems the most suitable legal justification to relinquish already contracted energy supply obligations and move to a newly balanced energy policy.