Spanish Prime Minister Mariano Rajoy. File photo: Pierre-Philippe Marcou

Madrid -

Spanish lawmakers are set to vote on Tuesday to shoot down Catalonia's quest for an independence referendum, setting the stage for a bitter sovereignty struggle.

In a showdown in the Spanish parliament, more than 80 percent of lawmakers will reject Catalonia's plan for a November 9 referendum, the national press predicted.

Prime Minister Mariano Rajoy's right-leaning Popular Party and the main opposition Socialists are both determined to prevent any breakup of Spain.

“End of the line,” read the front-page headline of the conservative daily ABC with a mock-up picture of a stone lion on a railway buffer at the end of a set of tracks.

It is unclear what Catalonia's next move could be if the referendum is refused.

Catalonia's regional head of government, Artur Mas, has in the past vowed to remain within the law.

He has also threatened to call snap regional elections as a form of plebiscite on the struggle for independence.

“It is clear that we will vote. It is impossible to think that in the 21st century Catalonia would be left without voting,” Catalan government spokesman Francesc Homs told a news conference.

Rajoy insists the vote would be illegal, since under Spain's constitution referendums on sovereignty must be held nationally and not regionally.

He has also warned that independence would be an economic disaster for both Spain and the northeastern region of Catalonia, one of the country's most productive but also most indebted regions.

Spain's Constitutional Court ruled last month that a region like Catalonia could not “unilaterally” call a referendum on its sovereignty.

But the Catalan government argues that a 2006 Catalan autonomy statute which was passed by Spain's parliament granted the region the power to hold referendums.

“There is a clear legal basis” for the plebiscite, said Homs.

The regional government faces strong pressure to push ahead with the referendum.

The Catalan National Assembly, a powerful pressure group, has gathered tens of thousands of signatures on a petition urging local leaders to “exhaust all of the paths” to a referendum.

“On November 9, we will vote. We will not renounce the referendum, because it is our dignity that is at stake, the dignity of Catalonia,” said the president of the group, Carme Forcadell.

The Catalan National Assembly on Saturday unveiled a “roadmap”, which calls for the region to declare independence from Spain by April 23, 2015 - the feast day of Saint George, the patron saint of Catalonia.

Last year on September 11, Catalonia's national day, hundreds of thousands of people formed a human chain across the region to demand independence in a rally organised by the group.

Proud of their distinct language and culture, many of Catalonia's 7.5 million citizens resent the redistribution of their taxes to other regions.

Catalonia's public debt stood at 57.1 billion euros ($78.5 billion) at the end of 2013, the highest of Spain's 17 autonomous regions.

Spanish lawmakers will begin debating Catalonia's request to hold the referendum at 4.00pm (14.00 GMT), with the vote expected several hours later.

The motion will be defended in the assembly by lawmakers from the Catalan president's ruling Convergence and Union alliance, or CiU, and its partners, the separatist Republican Left, or ERC.

Mas will not travel to Madrid to take part in the debate.

“Whatever happens, Catalonia finds itself again at a crossroads,” said Marius Carol, director of the region's leading newspaper, La Vanguardia, in an opinion piece on the morning of the vote.

“Let's hope that the tone and the speeches in parliament do not close doors.”

Rajoy said Monday he would like to resolve the crisis with Catalonia through dialogue.

“I never imagined anything else. I think we must talk,” he said.

But speaking on Sunday the secretary-general of Rajoy's People's Party, Maria Dolores de Cospedal, repeated the argument that “sovereignty cannot be negotiated and it cannot be shared”. - Sapa-AFP