The Spanish government of prime minister Mariano Rajoy insists the referendum – planned for 9 November – is illegal and should not take place.
Catalan leader Artur Mas signed the decree to call the referendum in a ceremony in the regional government headquarters in Barcelona, flanked by most of the regional leaders who support the vote.
“Like all the nations of the world, Catalonia has the right to decide its political future,” said Mas, an economist fluent in English, French, Catalan and Spanish.
Pro-independence sentiment in the economically strong region, where the Catalan language is spoken side-by-side with Spanish, has surged in recent years, fuelled by a sense the region deserves better fiscal and political treatment from Madrid.
Catalonia accounts for about a fifth of Spain’s economy, has a distinct culture and has long fought for self-rule.
The announcement came just over a week after Scotland voted against breaking away from the United Kingdom, by 55-45 per cent.
Rajoy, who was flying back from China yesterday, is expected to hold an emergency cabinet meeting within days.
The Spanish government plans to challenge a recently passed Catalan law permitting the referendum before the Constitutional Court, which it hopes will halt the vote.
Spain’s written constitution does not allow referendums on sovereignty that do not include all Spaniards, and experts say its Constitutional Court will rule the vote illegal.
Mas has suggested that if a referendum cannot be held he may call early elections, which could be turned into a proxy for a referendum.
“We are open to negotiating the conditions of the referendum until the last moment,” Mas said.
He is head of the ruling Convergence and Union coalition, comprising of the larger centrist nationalist Democratic Convergence of Catalonia (CDC) and its smaller counterpart, the Christian democratic, Democratic Union of Catalonia (UDC), both of which wish to separate from Spain.
While Mas called the referendum, hundreds of pro-independence supporters gathered in the square in front of the Catalan government building in Barcelona, with many wearing or waving pro-independence flags and chanting “independence”.
The crowd cheered when an electronic clock counting down the days until the referendum was set in motion on the side of a building overlooking the square.
“Today is a day to celebrate. We are very happy and satisfied that president Mas has called the referendum,” said Carme Forcadell, the leader of a pro-independence group that has organised pro-referendum rallies in the past three years.
Unlike the Scotland vote, where the Edinburgh Agreement stated that all sides would accept the result, a pro-independence result in a referendum in Catalonia would not ensure secession.
But Mas says it would give him a political mandate to negotiate independence with Madrid.
In the referendum, Mas wants to ask Catalans two questions: first, if they think Catalonia should be a state, and, if so, should it be independent.
Polls indicate most Catalans favour holding the referendum but are roughly evenly split on independence.
Pro-independence fervour fades when people are asked if they favour an independent Catalonia outside the European Union, as the region has been warned would happen. Barcelona has a booming tourist economy and uses the euro.
The referendum has stirred debate about whether the 1978 Spanish Constitution should be updated to accommodate Catalonia’s demands for more power while keeping the 17-
region country unified.
Separatist sentiment is also very strong in the northern Basque region.