In 2006 the region was given more devolved powers on things like healthcare and education but a move by Spain's Madrid-based Constitutional Court four years later to strike down some parts of the earlier agreement provoked anger among pro-independence Catalans.
On Monday, Catalonia leader Carles Puigdemont announced that he was not afraid of being arrested for organizing the illegal referendum vote regarding the region's independence from Spain which occurred on Sunday.
Catalonia's nationalist forces, which include factions from the far left as well as the right, gained a majority in the regional parliament in 2015 despite winning less than half of the vote.
Catalan authorities say around 900 people were injured and that of the almost 2.3 million votes counted, 90 percent voted in favor of an independent Catalan Republic.
More than 900 people were injured on Sunday after Spanish police attempted to halt the independence referendum by raiding polling stations, beating voters and firing rubber bullets at crowds.
Catalan authorities and the Spanish central government are at odds over the legitimacy of the vote.
Facebook messenger lite is coming to these countries
Facebook Lite sounds like a pretty great alternative, but has not expanded anywhere near as much as Messenger Lite . The Messenger Lite app uses simple and minimal visuals - which ensures that the app isn't heavy on graphics.
Mr Rajoy said the solution for the region "is the prompt return to legality and the affirmation, as early as possible, that there will be no unilateral declaration of independence, because that way greater evils will be avoided", he told Spain's EFE news agency.
Former Barcelona favourite Hristo Stoichkov on Thursday backed the independence referendum in Catalonia and denounced the violence that marred the banned vote. His televised statement on Tuesday evening was seen as paving the way for Madrid to take severe measures to block any attempts at independence in Catalonia. Most votes were counted despite police efforts.
With Spain's worst constitutional crisis in decades deepening, for the King to comment directly on a political event in or outside the country is nearly unprecedented.
The court said it had agreed to consider a legal challenge filed by the anti-secessionist Catalan Socialist Party.
Three full days after Catalonia's controversial independence referendum, a top European Commission official finally spoke out about the issue tearing Spain apart.
The wealthy northeastern region is home to Barcelona and boasts a distinct culture and language.
The court stated that such a move would be "a breach of the constitution", BBC reported Thursday.