Posted: Wed Jun 2, 2021 6:42pm
Not sure where you read that, but it is utterly, totally, completely 100% wrong.
90 days is the standard amount of time a tourist can spend in a country without extending a visa by some means - UK is the same (except for business stays and even then its restricted to 6 months and the person cannot appear to have "taken residence").
That aside, the 90 days in any 180 day period is set not by individual countries, but by the Schengen Treaty, of which 26 nations are signatories. Those nations can not decide unilaterally whether to implement 90 days or not - by signing the Schengen treaty they agreed to implement this. The Schengen treaty allows for borderless movement within the 26 nations that have signed up to it, i.e. no passports. This is why, despite being an EU member, passports had to be shown entering / exiting UK from / to EU - because UK wasn't a Schengen country.
This is also why its not a matter of Spain "negotiating" a new agreement with UK for longer than 90 days. Spain is bound by the Schengen treaty. An agreement such as that would by necessity introduce a hard border with France / Portugal (and newest Schengen member, Gibraltar) because you can't have someone staying legally longer than 90 days in one country, then moving across the border to say France where they would immediately be in breach of the Schengen ruling of 90 in 180 - the only way around would be for Spain to remove itself from the Schengen Treaty and negotiate new treaties with its neighbours, or for ALL 26 Schengen Nations to agree on extended stay for UK passport holders. Neither of those is happening.
Before anyone mentions New Zealand, yes, New Zealanders are not bound by Schengen rules, in that they can spend time in Spain and then immediately move to France, then Germany etc etc. This is because New Zealand negotiated those treaties with individual countries before the Schengen Treaty came into effect and so those original treaties are still honoured .... HOWEVER even New Zealanders are still limited to a 90 day stay in any of the signatory countries.