Thousands of people, many dressed in white, have rallied in Madrid and Barcelona, calling for talks to defuse Spain's worst political crisis for decades amid Catalonia's threat to secede.

The rallies in the Spanish capital and the Catalan city were held with the slogan "Shall We Talk?" in an effort to push politicians in both cities to end months of silence and start negotiating.

The wealthy northeastern region of Catalonia, with its own language and culture, has long claimed to be distinct from the rest of the country and on Sunday held a referendum on breaking away Spain, a vote the Constitutional Court had banned.

The Catalan authorities say that a majority of those who voted supported a split from Spain. Madrid says secession is illegal under the country's 1978 constitution.

Spanish authorities mobilised thousands of national police to stop Sunday's vote, leading to clashes with would-be voters as they tried to close polling stations in schools and remove ballot boxes. Nine hundred people were injured on polling day.

'Sort it out peacefully'

Sporting white shirts, protesters packed Barcelona's Sant Jaume Square where the Catalan government has its presidential palace, shouting "We want to talk!" and holding signs saying "More Negotiation, Less Testosterone!" and "Talk or Resign!"

"There has been an incredible amount of tension which has been building up since Sunday's referendum and people here are feeling that dialogue is sorely missed from all of this," said Al Jazeera's Sonia Gallego, reporting from the rally in Barcelona.

"We are here because we want the politicians to talk between them, we look for a solution," said a female protester. "Let them sort it out peacefully, and let each side demonstrate respect for another," added another one.

READ MORE: How would a Catalan secession affect FC Barcelona?

Gallego said similar rallies were taking place in other cities in Catalonia and across Spain, as well as in European capitals such as Berlin in Germany and London in the UK.

"There is a very real sense here with people who are attending this that politicians on either side of this issue are really turning down the concerns of the ordinary citizens," she said.

Even though 2.2 million Catalan voted - with 90 percent backing independence - the disputed referendum polled less than half of the electorate in a region that is home to 7.5 million people.

Catalonia's President Carles Puigdemont has vowed to make good on the results of the vote. Spanish Prime Minister Mariano Rajoy warned that the vote was illegal and has promised that Catalonia is going nowhere.



"We have to find a new way forward," said Miquel Iceta, the leader of Spain's Socialist party in Catalonia. "It's the moment to listen to the people who are asking for the problem to be solved through an agreement, and without precipitated and unilateral decisions."

In a separate rally in Madrid's Colon Square, thousands clamoured for the unity of Spain and against any attempt by the northeastern region to break away. The crowd bristled with Spanish flags.

The calls for dialogue and unity come after a traumatic week, with riot police storming several polling stations in an unsuccessful attempt to impede the referendum. Instead, hundreds of voters were left in need of medical attention.

'N ew opportunity for dialogue'

The bloodied vote was followed by a strike on Tuesday across Catalonia to protest the police violence. Spain's King Felipe VI weighed in, sharply criticising the Catalan government and parliament and accusing them of breaking the law.

The police violence drew widespread condemnation and forced the government to issue an apology on Friday, although tensions continued to rise after reports of plans for the Catalan parliament to vote on a unilateral declaration of independence on Tuesday.

READ MORE: Spain's top court blocks Catalan parliament's meeting

Puigdemont and his separatist supporters were struck a blow when Catalonia's top two banks, CaixaBank and Banco Sabadell, as well as the energy giant, Gas Natural, announced they were relocating their headquarters from Catalonia to other parts of Spain.

Other companies are considering such a move to ensure that the region's possible secession would not knock them out of the European Union and its lucrative common market.

Spain's Minister of Public Works Inigo de la Serna said on Saturday that "the companies will keep leaving and it's exclusively the fault of the members of the regional government".

The warnings by the business sector have coincided with the first calls from within Puigdemont's government to hold off on a declaration of independence.

Santi Vila, Catalonia's regional chief for business, told Cadena SER Radio late on Friday that he's pushing for "a new opportunity for dialogue" with Spanish authorities.

"We have to give it one more chance, maybe the last chance, and perhaps the only way that can happen is to start with a ceasefire," Vila said.

Vila said he would like to see Spanish authorities return powers to the region which they have assumed in recent weeks, including control of a large part of its finances.

It is unclear how widespread Vila's moderate position is inside the Catalan government, which is being pressured by separatist grassroots groups and the far-left party CUP to declare independence soon.