One of Spain's biggest and richest regions, Catalonia will defy Madrid on Sunday when it holds a symbolic vote on whether it should break away as an independent state.

Despite the fierce opposition from Madrid, Catalan leaders have stuck by their vote plan in a constitutional standoff unprecedented in post-Franco Spain.

Knocking on neighbors' doors in central Barcelona, 46-year-old engineer Jaime Gutierrez and retiree Toni Vinas, 74, are out canvassing their fellow Catalans to vote Yes to independence from Spain.

Going door to door in the neighborhood around the city's Sagrada Familia Cathedral, they are just two in an army of volunteers mobilized for the ballots in the Catalonia region on Sunday in defiance of legal challenges by Madrid.

The government of Spain's wealthy Catalan region put itself on a collision course with Madrid Tuesday by vowing to press ahead with a symbolic independence vote this weekend despite a court-ordered block.

Catalan government spokesman Francesc Homs said "everything is ready" for Sunday's referendum, which will be run by volunteer poll-watchers and involve same-day registration.

Catalonia's president on Saturday formally called a referendum to decide whether Spain's richest region should be independent, in a defiant move immediately rejected by Madrid as anti-constitutional.

Shortly after Artur Mas set the vote for November 9, the Spanish government said the referendum would not be allowed to take place, with Deputy Prime Minister Soraya Saenz de Santamaria warning no one "was above the national will of the Spanish people."

Vast crowds of revelers in high heels, wigs and figure-hugging dresses cavorted in the streets of Madrid on Saturday in what is billed as the biggest gay pride parade in Europe.

Tens of thousands crammed one of the Spanish capital's broad central avenues, the Paseo del Prado, in the early evening to the din of drums and whistles in a parade scheduled to last seven hours.

Madrid's top art museum the Prado unveiled a major show Monday about the master painter El Greco, exploring his influence on modern greats such as Francis Bacon and Jackson Pollock.

"El Greco and Modern Painting" is part of a year-long series of big exhibitions to mark the 400th anniversary of the Greek-born master's death.

Spanish police on Sunday arrested a member of the armed Basque separatist group ETA suspected of belonging to a unit that killed several police officers in the 1980s, the interior ministry said.

Police detained Maria Jesus Elorza Zubizarreta, 66, at Madrid's Adolfo-Suarez Barajas airport under a European arrest warrant issued by France in 2006, the ministry said in a statement.

Spain set its future King Felipe VI on the path to the throne Tuesday, launching an unprecedented handover of the crown in the face of a breakout of anti-royalist protests.

One day after 76-year-old King Juan Carlos declared an end to a four-decade reign that guided Spain from dictatorship to democracy, the government met to ponder the first succession in post-Franco history.

Scientists will start scanning Monday with a radar the floor of a Madrid convent where they hope to find the body of Spanish writer Miguel de Cervantes, author of "Don Quixote".

They said on Friday they were ready to begin searching in the Convent of Trinitarians to identify the writer, who died in poverty despite creating one of the landmarks of Western literature.

Hundreds of chanting demonstrators marched through the streets of Madrid on Thursday to protest against alleged police violence at a large anti-austerity demonstration in the Spanish capital last month.

The protesters accused police of brutality during demonstrations by tens of thousands on March 22.