BARCELONA, Spain — Thousands rallied in Madrid and Barcelona on Saturday in a last-ditch call for Spanish and Catalan leaders to stave off a national crisis 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 lawmakers in both cities to end months of silence and start negotiating. Attendees respected the organizers’ call to not bring the Spanish or Catalan flag.

Catalonia’s regional president Carles Puigdemont has vowed to make good on the results of last Sunday’s disputed referendum on secession won by the yes side. Spanish Prime Minister Mariano Rajoy warned that the vote was illegal and has promised that Catalonia is going nowhere.

Pro-union forces will try to generate momentum on Sunday in a protest in Barcelona.

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.

Even though 2.2 million Catalan voted – with 90 percent backing independence – the referendum polled less than half of the region’s electorate.

Puigdemont declared he would seek a declaration of independence in the regional parliament anyway.