BARCELONA, Spain — In a major escalation of Spain’s territorial conflict, Catalan lawmakers approved the region’s independence on Friday, a move that was quickly countered by a vote in the Spanish Senate authorizing the government to take direct control of the fractious region and remove its separatist leadership.

The dueling actions set up a potential showdown over the weekend, as Spain careened into its greatest constitutional crisis since it embraced democracy in 1978.

The Senate voted 214 to 47 to invoke Article 155 of Spain’s Constitution, granting Prime Minister Mariano Rajoy a package of extraordinary powers to suppress Catalonia’s independence drive.

In a speech on Friday before the vote, Mr. Rajoy had said he had “no alternative” because the Catalan leader, Carles Puigdemont, and his separatist cabinet had pursued an illegal and unilateral path that was “contrary to the normal behavior in any democratic country like ours.”

Undeterred by the government’s threat, and after a bitter debate, separatists in the Catalan Parliament passed a resolution to “create a Catalan republic as an independent state.” Lawmakers opposed to independence walked out of the chamber in protest before the vote.

Mr. Puigdemont came close on Thursday to calling early regional elections, but dropped the idea and instead told Catalonia’s Parliament that it would make a decision on independence the next day. He leads a fragile separatist coalition that has 72 of the body’s 135 seats.

During the debate that preceded the vote, Catalan lawmakers traded accusations and in turn described the occasion as “historic” and “happy,” or else “tragic” and a serious violation of Spain’s Constitution.

Addressing the Catalan Parliament in Spanish, Carlos Carrizo, a lawmaker from Ciudadanos, a party that opposes secession, told Mr. Puigdemont and separatist lawmakers that, far from creating a new Catalan republic, “you will go down in history for having fractured Catalonia and for sinking the institutions of Catalonia.