Foreign affairs minister Josep Borrell has issued the assurance that UK citizens in Spain, estimated to be around 400,000, will be granted residency even if they don't currently have permanent residency. Many UK citizens have the permanent residency certificate, but many do not.
It is understood that UK residents in Spain will need to apply for a foreigner identity card. There will be plenty of time to do this - up to the end of next year.
The arrangements that the Spanish government is outlining are on the condition that the UK reciprocates and offers similar measures for Spanish citizens.