MADRID - Spain erupted with its biggest fiesta in memory Monday when its football team returned to a jubilant nation after winning the World Cup, giving elated Spaniards a break from months of economic gloom and political squabbling as nationalist regions fought for greater autonomy from the central government.

Hundreds of thousands of people -- if not more -- jammed Madrid's historic avenues as an open air bus ferried the national team down stately avenues to cheers from Spaniards decked out in a sea of red and yellow, the colors of the Spanish flag.

The celebration in Madrid, where national unity is at its strongest, was expected. But there were striking examples of support from unlikely places: The well-off Catalonia region, which has long sought greater autonomy, and the separatist Basque region, where anything pro-Spain is often shunned.

The massive Madrid street party came after players visited Madrid's Royal Palace, normally used only for dreary state affairs. But team chatted and drinks with King Juan Carlos, who hugged many players and gave coach Vicente del Bosque friendly punches on the cheek and the chest.

"You are an example of sportsmanship, nobility, good play and team work," said the king.

Team members then traveled to government headquarters, where they were greeted by Prime Minister Jose Luis Rodriguez Zapatero, ministers and hundreds of ecstatic children invited to the event.

"They won the cup but it belongs to all Spaniards," shouted a delighted Zapatero.

Goalkeeper and captain Iker Casillas said the victory meant "Spain's name will be on top of the world for the next four years."

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Next came an open-air bus ride through Madrid's historic center, the epicenter of the celebration for the second day in a row. Crowds overflowed into the street and surrounded the team bus, virtually all sporting the red and yellow national colors along the five-kilometer (three-mile) route as the bus crawled through the crowd with the players waving and raising the gold World Cup trophy into the air.

At the route's end, firefighters hosed down fans sweltering in 36 Celsius (96 Fahrenheit) evening heat.

As the parade snaked down the Gran Via in the heart of Madrid, Spanish air force fighter jets flew overhead spewing out the colors of the national flag.

On the bus, the players waved flags and saluted the screaming fans below. Casillas raised a red and yellow carton cutout of Octopus Paul, the mollusk from the German zoo that predicted Spain's victory

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Such was the multitude clogging the streets and avenues that the team arrived more than hour late at the finishing esplanade. Madrid town hall urged no more people to go to the park area, as it had already reached its 150,000 capacity.

"For us Spaniards this is important. It is a way of showing that Spain is united," said Roberto Lopez, 48 Madrid car salesman. "It's not Galicia on one side and Catalonia on the other.

Juan Mateos, a 35-year-old civil servant described the celebrations as "a bit of anesthetic to forget about our problems."

The party started when the players' plane touched down, flying Spanish flags from its cockpit windows, with dozens of airport workers cheering from the runway. It taxied to a stop as cars driving by on nearby highways blared their horns in support.

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A roar of approval rose as Casillas stepped from the plane and raised the trophy. The crowd chanted "Campeones! Campeones!" (Champions! Champions!). Then the players in their team jerseys walked from the plane to a waiting Spanish football federation bus without commenting to journalists.

The spectacle was "very important, it helps us forget a lot of things, like the economic crisis, for example, or people's domestic issues," said Javier Sanchez, a 42-year-old photographer from Madrid.

But will the ecstasy last? Could this be Spain's moment to unite under a single flag? Or is it a fleeting instance of patriotism following near economic chaos when the country was targeted as one of the European nations most likely to default on debt like Greece?

Spain has been depressed by a debt crisis, 20 percent unemployment and nationalist regions fighting to separate from the country or at least win much greater autonomy and near-nation status.

World Cup champions Country Titles won (year) Brazil 5 (’58, ’62, ’70, ’94, ’02) Italy 4 (’34, ’38, ’82, ’06) Germany 3 (’54, ’74, ’90) Argentina 2 (’78, ’86) Uruguay 2 (’30, ’50) England 1 (’66) France 1 ('98) Spain 1 ('10)

While the spotlight was on Madrid, the win led to a rare sight in the Catalonia region's capital of Barcelona: Spanish flags waving side-by-side with Catalonia's own red and yellow flag.

"It has been very strange, but now it is being tolerated," said Saray Lozano, a 31-year-old taxi driver from Barcelona. "If it weren't for football, you might get rocks thrown at you" for displaying Spain's national symbol.

About 75,000 people celebrated the win in Barcelona, and about 2,000 people waved Spanish flags and wore the team's football jersey in the Basque city of Bilbao -- actions rarely seen because of the violent campaign led by the separatist group ETA since 1968 to gain independence from Spain.

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Just wearing the jersey on the streets of Bilbao before the win was a sure way to get insulted and risk assault.

But experts said the idea of Spain overcoming its internal divisions and economic woes because of the World Cup is unlikely to become reality. In and around Bilbao, authorities blamed sabotage for an electrical outage that canceled an open air broadcast of the final game, and several people supporting the national team were attacked by separatists.

"I wouldn't have thought the euphoria over the football will last very long," said Paul Preston, a Spain expert and history professor at the London School of Economics.

As for Spain's fragile economy, the win "may soften the blow of the economic news, but it won't have a long-lasting effect," Preston said.

Joan Foguet, a Barcelona-based journalist for the leading Spanish newspaper El Pais, said Catalonia has a "schizophrenic" relationship with the national team -- and attributed the burst of enthusiasm to the fact that the team played well.