The president of Spain's Catalonia region has signed a decree calling an independence referendum on November 9, putting him on a collision course with the central government, which says such a vote is illegal.

The wealthy northeastern region, which accounts for about one-fifth of Spain's economy, has its own language and distinct culture and has long fought for self-rule.

Catalonia has been part of Spain since its genesis in the 15th century, when King Ferdinand of Aragon and Queen Isabella of Castile married and united their realms.

Today, the Catalonian economy is bigger than the entire Portuguese economy and generates 20% of Spain's wealth. According to polls, a large majority of Catalans want to hold a referendum on independence.

Until recently, comparatively few Catalans wanted full independence, but Spain's painful economic crisis has seen a surge in support for separation. Many Catalans believe the affluent region pays more to Madrid than it gets back, and blame much of Spain's debt crisis on the central government.

The region's president, Artur Mas, signed the decree yesterday in a solemn ceremony in the Catalan government offices in Barcelona - the gothic Generalitat Palace - surrounded by his government and political allies in his campaign for independence.

"Catalonia wants to speak. Wants to be heard. Wants to vote. Now is the right time and we have the right legal framework to do so," Mas said in a speech in Catalan, Spanish and English immediately after the signing ceremony.

Madrid has vowed to block a ­referendum. On Friday, Spanish deputy prime minister Soraya Saenz de Santamaria said the cabinet would meet tomorrow to formalise an appeal against the vote. The objection would then be handed to the Constitutional Court, suspending the vote until a final ruling on its legality, which could take years.

Spain's central government says a Catalan independence referendum would violate the country's 1978 constitution, drawn up on Spain's transition to democracy.

The ­Catalan leader has hinted that if the government blocks the vote, he could call early regional elections that would effectively act as a plebiscite on the issue.

Mas is under pressure from separatist coalition partners to go ahead with a referendum even if it is declared illegal, although he has himself said he would not do anything that is against the law.

Madrid's refusal to allow a vote has angered many Catalans, even those who favour continued union with Spain.

Hundreds of thousands of people marched in Barcelona earlier this month demanding the right to hold a referendum.