(3)In order to enable the effective and efficient comparison and aggregation of data across trade repositories, XML format templates and XML messages developed in accordance with ISO 20022 methodology should be used for access to data and for communication between the entities referred to in Article 81(3) of Regulation (EU) No 648/2012 and the trade repositories. This should not exclude the possibility that trade repositories and the relevant entities may agree amongst themselves to provide access or to communicate using a different format in addition to XML.