The rich northeast region wants to be called a nation and have greater control over its own taxes, paying less towards poorer parts of Spain.

But other regions have condemned the plan, calling on their people to boycott goods and services from Catalonia.

The debate leaves José Luis Rodríguez Zapatero, the Prime Minister, with a dilemma: whether to honour his election pledges and grant key Catalan coalition partners autonomy from Madrid; or to heed calls from within his own party and try instead to stifle independence claims.

Under a statute devised by Catalonia’s regional politicians last month, the region would also have more control over police, the judiciary, the prison service, ports and airports. Catalonia would administer Euro- pean Union funds and Madrid would have to ask permission if international issues affected the region.

The breakaway plan has split Spain, incurring the anger of many who believe that the Catalans will leave poorer areas without vital financial support.

For Señor Zapatero the political risks are high. His minority Government depends for support on Catalan regional nationalist parties. If he does not concede enough ground over the statute he faces losing their support — in which case he may have to look elsewhere for help in getting vital legislation, such as next year’s budget or promised reforms of the Spanish Constitution, through parliament.

But if he gives away too much, he faces losing the support of many parts of his own Socialist Party.

Señor Zapatero has already said that he will modify demands for greater tax powers.

But there are signs of splits in the Spanish Socialist party. Juan Carlos Rodríguez Ibarra, the Socialist president of Extremadura, one of Spain’s poorest areas, said that the plan would create a Spain of “haves and have-nots”.

Some politicians have gone further, urging people through radio broadcasts to boycott cava, the sparkling wine produced in Catalonia, to withdraw their money from Catalan banks, cancel skiing holidays in the Pyrenees or abandon shopping trips to Barcelona.

Mariano Rajoy, leader of the conservative opposition Popular Party, has dismissed the statute as unconstitutional and called on Señor Zapatero to return the 111-page document to Catalonia.

Spain’s business community is worried by the prospect of more red tape that greater independence would bring. A recent report said that new businesses in Spain suffered from one of the worst levels of bureaucracy, on a par with Botswana. Jaime Caruana, governor of the Bank of Spain, said that Catalonia’s bid for independence would threaten the efficiency of the Spanish economy and the wellbeing of all Spaniards.

If Catalonia is seen to have won more power than expected, it could provoke more calls for independence.

The Spanish parliament has already rejected a proposal by the Basque region to break away from Spain.

Catalonia, like all of Spain’s regions, already enjoys considerable autonomy from Madrid under the 1978 Constitution. But since the death of General Franco, who banned the Catalan language, demands for greater independence have been growing.

Now many sectors of society in Catalonia, including Barcelona Football Club, have shown public support for the latest independence plan.

But for others, Catalonia’s politicians have gone too far with their demands.

Josep Ferrer, honorary president of Freixenet, Spain’s largest cava producer, said: “We are worried about the impact of the present political situation on sales.”

This year, after Catalan nationalists called for a boycott of the Madrid 2012 Olympic bid, cava sales fell dramatically.

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