Madrid: Spain's autonomous region of Catalonia Sunday decided to vote in an informal poll on independence as Prime Minister Mariano Rajoy urged the people to return to "sanity", media reports said.
Urging the people for talks "within the legal framework of the constitution", Prime Minister Rajoy said the vote would be "neither a referendum nor a consultation nor anything of the sort", BBC reported.
The Spanish judiciary has ruled the vote unconstitutional but Catalan leader Artur Mar warned against any attempt to disrupt it.
A "Yes" vote in the referendum will give Catalan President Artur Mas the mandate to negotiate independence with the Spanish administration.
Ballot boxes were set up Saturday at schools and town halls across Catalonia, which accounts for around one-fifth of Spain's economy, more than it gets back through the central government funds.
Catalonia moved towards greater autonomy in 2006 when it formally adopted a charter that assigned it the status of a "nation".
However, the nationhood claim was overruled by Spain's Constitutional Court in 2010.
Economic and cultural grievances have fuelled Catalan nationalism.