Must Articles 45 and 48 TFEU, Article 4 TEU, Article 11 of Annex VIII to the Staff Regulations of Officials [of the European Union] and Article 8 of Annex IIIa to the Conditions of Employment for Staff of the European Central Bank be interpreted as precluding a set of national rules or a national administrative practice which does not allow a worker who is a national of a Member State who has paid contributions to the national social security institution and who currently works for an EU institution, such as the ECB, to transfer to the pension scheme of that institution the pension contributions credited to the social security scheme of his or her own State?

Based on the answer to the question set out above, must it be possible to exercise the right to transfer contributions even in the absence of national implementing legislation or a specific agreement between the Member State of which the worker is a national or the worker’s pension institution, on the one hand, and the EU institution, on the other?