カタルーニャ語圏
The Spanish Constitution of 1978 contains a clause forbidding the formation of federations amongst autonomous communities. Therefore, if it were the case that the "Països Catalans" idea gained a majority democratic support in future elections, a constitutional amendment would still be needed for those parts of the "Països Catalans" lying in Spain to create a common legal representative body, even though in the addenda to the Constitution there is a clause allowing an exception to this rule in the case of Navarre, which can join the Basque Country should the people choose to do so.