Spanish Prime Minister Mariano Rajoy on Saturday announced Madrid would seek to sack Catalonia's regional government, replace its ministers and call for early elections, marking an unprecedented move to take control of the autonomous region following its threat to secede. 

The decision to trigger Article 155, a never-before-invoked part of the constitution, came after Catalan leader Carles Puigdemont failed to back down from threats to declare independence.

"It was not our wish or intention. It never was," Rajoy said. "But no democratic government can allow the law to be violated."

Read more: Spain's Article 155: The constitution's 'nuclear option'

Rajoy said he did not seek to dismantle Catalan autonomy, but to "restore democracy" and remove the people who had brought it "outside of the law." 

Rajoy wants to:

- Replace Catalonia's senior government officials with his ministers

- Call regional elections to be held within six months

- Control the region's police force, finances and public media

In response, Puigdemont slammed Rajoy in a speech later on Saturday, saying the steps being taken were "the worst attack against the institutions and the people of Catalonia since the military dictatorship of Francisco Franco."

During Franco's 1938-75 rule, Catalan autonomy and identity were suppressed.  The democratic constitution that emerged from dictatorship granted Catalonia a degree of autonomy in 1979.

Puigdemont called on the Catalan parliament to meet immediately to debate how best to counter the national government's decision.

Catalan parliament speaker Carme Forcadell went so far to accuse Madrid of attempting to carry out a coup.

"Mariano Rajoy has announced a de facto coup d'etat with the goal of ousting a democratically elected government," Forcadell said, adding that the decision was "an authoritarian blow within a member of the European Union."

Massive protest

Following the announcement, hundreds of thousands of people took to the streets of Barcelona to protest Rajoy's plans.

They also called for the release of two activists, Jordi Sanchez and Jordi Cuixart, who are in jail awaiting possible sedition charges.

Podemos: 'In shock'

Rajoy's conservative Popular Party has a majority in the Senate and most opposition parties support protecting Spanish unity, meaning a vote to invoke Article 155 is likely to pass. A vote is expected by next Friday.

However, the left-wing Podemos party slammed Rajoy's announcement and vowed to push the prime minister out of power.

"We are in shock about the suspension of democracy in Catalonia," said Pablo Echenique of Podemos.

'Return to legality'

The unprecedented step of seizing powers from Catalonia's separatist government came after Puigdemont claimed a mandate to declare independence earlier this month.

Separatists have urged Puigdemont to declare independence should the government invoke Article 155. But Spain's chief prosecutor said authorities are prepared to charge Puigdemont if he declares independence.

'Extreme situation'

Since a disputed independence referendum earlier this month, Madrid and Barcelona have been locked in a political crisis, considered the worst since Spain's transition to democracy.

"We tried in every way to avoid a difficult situation, but you will understand that ... we have arrived at an extreme situation," Rajoy said at a press conference during an EU summit in Brussels earlier this week. 

Read more: Beyond Catalonia: Separatist movements in Western Europe

Catalan leaders' actions go "directly against the basic principles of the European Union, and this is why nobody should be surprised that the leaders of the European Union are supporting the Spanish position," he said. 

Dreams of independence

Puigdemont's government has claimed that roughly 90 percent of voters cast their ballots in favor of independence. However, turnout was only 43 percent, with many pro-union Catalans saying they stayed away from the controversial vote.

Read more: In Catalonia, language and identity go hand in hand

After the vote, Puigdemont offered a symbolic declaration of independence but suspended the divorce process, prompting Rajoy to issue a deadline for clarification on the Catalan government's position.

Minutes before Thursday's deadline, Puigdemont refused to depart from his secessionist discourse, instead vowing to advance independence if Rajoy's government were to dismiss talks and trigger Article 155.

cw,ls,es/aw (AFP, dpa)