The Fukushima Daishii nuclear disaster lead countries to change their nuclear approaches changed drastically. Although being a traditionally pronuclear country, France followed this tendency by approving a strategy to reduce its nuclear portfolio. Under European law this development is permitted by the right to right to determine its own energy mix include in Article 194(2) of the Treaty of Functioning of the European Union. However, other European legislation that may influence this decision was not considered. This legislation may limit this right and the policy by itself. This article tries to show how, although possible due to the right to determine its own energy mix, the French nuclear strategy may be unlawful under the EU law, namely the European Atomic Energy Community Treaty and the primary and secondary legislation regarding Security of Energy Supply.