Thursday’s vote could fan the flames of an already impassioned independence drive especially if it garners the two-thirds majority.

However, according to Spain’s constitution, only the central government in Madrid can call a referendum.

Catalan President Artur Mas has urged European Union prime ministers to support the region’s push for independence.

But the rightist government of Spanish Prime Minister Mariano Rajoy has threatened to block a referendum on self-rule, promised for November 2014 by the Catalan regional government.

The referendum would ask two questions: “Do you want Catalonia to be a State?” and “Do you want that State to be independent?”

In recent years, massive rallies have also been held to claim the self-determination right for the region.

More than one million Catalans took to the streets across Spain in September last year and joined hands to form a 400-kilometer (250-mile) human chain in a major drive for independence from Spain.

Polls indicate about half of Catalonia’s 7.5 million inhabitants want to break away from Spain.