I don't know the exact details but I didn't think Iceland was in Europe, the UK wanted to rush them in so that those rules could apply:
https://en.wikipedia.org/wiki/Accession_of_Iceland_to_the_Eu...
https://en.wikipedia.org/wiki/Accession_of_Iceland_to_the_Eu...
Later, after the shit hit the fan, Iceland did apply for EU membership and negotiations begun. Iceland later withdrew their application.