While for the Basque nationalist movement, the external actors have a legitimizing function that add pressure to the Spanish institutions to find an acceptable solution to the Basque question, in the case of Catalonia, the Catalan nationalists are much more exposed to the position taken by actors outside of Spain.
The analysis from the historical perspective also shows that some external actors (particularly, international organisations) have evolved from being entities that could legitimise the claims in favour of secession towards a form of referee that determines the chances of the process to succeed due to the transformation of the supranational entities themselves. This is particularly clear in the case of the European Union that occupies a privileged position in the recent developments occurring in Catalonia.