(27)In order to comply with the principle of proportionality and to avoid excessive administrative burden, the possibility for competent authorities and, where relevant, resolution authorities, to waive the requirements relating to the preparation of the recovery and resolution plans on a case-by-case basis should be allowed in the limited cases specified in this Directive. Such cases comprise institutions affiliated to a central body and wholly or partially exempt from prudential requirements in national law in accordance with Article 21 of Directive 2013/36/EU and institutions which belong to an institutional protection scheme in accordance with Article 113(7) of Regulation (EU) No 575/2013. In each case the granting of a waiver should be subject to the conditions specified in this Directive.