Spain's Socialist leader is set to meet the Pope's representative today amid a storm of controversy over the Roman Catholic Church's calls to oust him from power.

José Luis Rodríguez Zapatero plans to tell Monsignor Manuel Monteiro de Castro, the Papal Nuncio, that the Church must respect the elected Government and refrain from campaigning for the opposition before the March 9 general election.

“They will address the recent difficulties and clashes between the Church and the Government”, a government official said.

Spanish bishops waded into the election campaign two weeks ago when they effectively directed Spaniards to vote against the Government and in favour of the conservative Popular Party.

In a paper setting out the Church's “moral guidance” for voters, the Episcopal Conference attacked the Government's moves to legalise gay marriage, make divorce easier and remove religious education from the compulsory school curriculum.

Those policies have all been sources of friction with the Church in the past. This time the bishops went further, condemning the Government for its attempts to negotiate a peace treaty with the Basque separatist group, Eta. It also hit out at a law that aims to redress the grievances of the victims of General Franco's four-decade dictatorship in Spain.

“While it is true that Catholics may support different political parties ... it is also true that not all their programmes are equally compatible with faith and the demands of Christian life,” the bishops said.

The Government reacted with fury, accusing the bishops of wishing to return to the Franco era, when they held sway over the Spanish population. It also hinted that it may revisit a 2006 agreement with the Vatican that safeguarded state funding for the Catholic Church in Spain.

“The bishops' alliance with the Popular Party will fundamentally alter the relationship with the Government,” the Socialist Party leadership cautioned.

Relations between the Church and the Government took a turn for the worse in December, when a 150,000-strong march in support of the family turned into an anti-government tirade. Bishops told the crowd that the “family is under strong attack” and gave warning that under Mr Zapatero's rule “we are heading towards the end of democracy”.

Their condemnation of Mr Zapatero's efforts to negotiate an end to Eta's four-decade violent campaign for an independent Basque state added fresh fuel to the fire. “The bishops have no right to use terrorism as a campaign issue,” said Mr Zapatero, adding that they had clearly overstepped their role.

Critics also accused the bishops of hypocrisy, given that they did not object to similar efforts in 1999 by José María Aznar, the Conservative former Prime Minister. The Church played an active role in those negotiations: the Bishop of San Sebastián, Juan María Uriarte, worked as a mediator with the Vatican's blessing. Catholic supporters of the Socialist Party were also angry. “It is one thing to put forward the Catholic viewpoint, and quite another to enter politics and take sides,” said Carlos García de Andoin, head of the Christian Socialists group. “This should not be the Church's role.”

Relations between the Church and the Left have been poisoned since the Civil War in the 1930s, when Communist and Anarchist irregulars burnt churches and killed thousands of priests. The Spanish Church strongly supported Franco's Fascist dictatorship and some bishops were even pictured in stiff-armed salutes.

Thorny issues

— Gay marriage: In 2005 Spain became one of only three countries to legalise full, same-sex marriage

— Religious instruction: The Socialists scrapped plans to make religious education compulsory in schools

— Express divorce: New fast-track divorces are regarded by the Church as an attack on the traditional family

— Citizenship classes: The Church regards the introduction of the EU-mandated course as an effort to usurp its role in the moral education of children

— Peace process: Bishops say that negotiations with Eta were immoral

— Historic memory law: The Church says that efforts to redress grievances of victims of Franco's regime are “historical manipulation”

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