167It should be added that the possibility, referred to in the case-law of the Court of Justice cited in paragraph 162 above, of interpreting a provision of secondary legislation in the light of an international agreement, does not arise where the provision is clear and unambiguous and thus does not require any interpretation, as the expression ‘so far as is possible’ attests. If that case-law were applicable in such a case, the principle of consistent interpretation of secondary EU law would serve as the basis for an interpretation of that provision contra legem, which cannot be permitted (see, by analogy, judgment of 13 July 2018, Confédération nationale du Crédit mutuel v ECB, T‑751/16, EU:T:2018:475, paragraph 34). For the same reason, where the provision of secondary legislation at issue is unambiguous, a consistent interpretation cannot be applied when all possible interpretations of that provision are contrary to the higher-ranking rule.