It is amazing how few people know this.
Our daughter lives in Munich and is waiting to hear that she has been granted German citizenship.
Both Germany and France allow dual citizenship, thank goodness.
I’m not sure if this information is still actual (I can not believe otherwise) but if you have to relinquish your British passport & nationality for these kind of procedures, once you have obtained the nationality of the country desired, just pop into the nearest British Consulate & get a new British passport.
Spain does not allow dual nationality.
As I wrote _“I’m not sure if this information is still actual” (I can not believe otherwise)_Things may have changed though? But having worked for HMG in the FCO I have knowledge of this happening quite often. The saying was, & still maybe that "once a Brit always a Brit as far as British admin is concerned. Maybe this chap should go & have a chat with a Consulate Official.
Hang on - don’t they require you to relinquish your UK citizenship which is a formal process resulting in a document - a “declaration of renunciation” - to prove you have done so and, presumably, to submit that document to the Spanish authorities?
That’s a bit more than just handing your passport over and then nipping round to the consulate to get a new one.
Seems a bit lax of them to have such a gaping loophole.
I have no idea how, but know it has.