Spain took formal direct control of Catalonia on Saturday, dismissing the region's defiant separatist government a day after lawmakers passed a declaration of independence for the prosperous northeastern region.
Madrid and Barcelona have been at odds after the October referendum in Catalonia, where some 90 percent of voters backed the idea of the secession.
The Senate is expected to pass the emergency measures, which include sacking the Catalan president. Tens of thousands celebrated in Barcelona and other Catalan cities after Friday's independence declaration, which analysts say the region has no legal power to execute.
Refusing to comment on Puigdemont's televised address, Rajoy's office said on Saturday that his actions will be a judicial affair from now on and that the December 21 election would be the way "to return dignity to the Catalan institutions".
An official state bulletin (in Spanish) handed control of Catalonia to Spain's Deputy Prime Minister, Soraya Saenz de Santamaria.
He added: "We continue persevering in the only attitude that can make us winners".
Spain fired Catalonia's regional leaders on Saturday morning. Behind him there were the Catalan and European Union flags, but not the one from Spain. The firing of Josep Lluis Trapero, the highest-ranking officer of the Mossos d'Esquadra regional police, follows yesterday's dismissal of Catalonia's president, his deputy, all ministers, and the entire parliament.
Catalans had a range of powers in many policy areas from culture and environment to communications, transportation, commerce and public safety.
Officials in Europe are speaking out against Catalonia's declaration of independence.
There were pro-unity demonstrations too, with protesters in Barcelona waving Spanish flags and denouncing Catalan independence.
Spain's government has said they could be charged with usurping others' functions if they refuse to obey, which could throw the region into further turmoil by prolonging a monthlong standoff. Some accused Catalonia's leaders of treason.
Speaking on Catalan television TV3, Puigdemont said he does not recognize the decisions of the Spanish central government and will continue "to work to build a free country".
Many Catalans feel they pay more to Madrid than they get back, and there are historical grievances, too, in particular Catalonia's treatment under the dictatorship of General Franco.