59The Court has consistently held in this regard that it is incumbent on the national courts to safeguard the rights of individuals when faced with any disregard by national authorities of the prohibition on the implementation of aid, which is set out in the final sentence of Article 93(3) of the Treaty and is directly effective. Such disregard, if relied on by individuals and confirmed by the national courts, must lead those courts to draw from it all the consequences in accordance with their national law, without their decisions, however, implying an assessment of the compatibility of the aid with the common market, which is a matter within the exclusive competence of the Commission, subject to review by the Court (see CELBI, cited above, paragraph 23, Case C-354/90Fédération Nationale du Commerce Extérieur des Produits Alimentaires and Syndicat National des Négociants et Transformateurs de Saumon [1991] ECR I-5505, paragraph 14, and Case C-39/94SFEI and Others [1996] ECR I-3547, paragraphs 40 and 42).