The Regulation (EU) No. 910/2014 the european parliament and council of 23 july 2014 (link to https :// www.boe.es/doue/2014/257/L00073-00114.pdf), on the electronic identification and confidence in electronic transactions in the internal market and repealing directive 1999/93/ec (regulation eIDAS) establishes the conditions under which member states must recognize the means of electronic identification of natural and legal persons belonging to a system of electronic identification notified of another member state and the standards for the services of trust and a legal framework for electronic signatures, electronic seals, stamps electronic time, electronic documents, delivery and electronic services certified certificate for authentication of websites.
As regards electronic identification, the regulation establishes the obligation to acknowledge, in september 2018 the identification schemes reported by other member states for electronic access of citizens (legal and natural persons) to public services. In practice, this means that, once a Member state has announced its intention that a certain electronic identification system is recognised by the rest, the citizens of that state may use the identification system (e.g. the DNI-e in the case of Spain) to access to public services online offered by other states in the same conditions as those States which offer their own citizens.
For more information on this regulation and its future implementation in Spain you can consult the technical note: “ The european regulation eIDAS "