Pablo Llarena, the Spanish Supreme Court judge who is presiding over the trial against Mr. Puigdemont and other Catalan politicians, has said that Spain’s judiciary could take the case to the European Court of Justice if Germany blocked Mr. Puigdemont’s extradition on the charges sought by Madrid. There was no immediate response from Judge Llarena to the German decision.

The court’s decision is in line with a preliminary ruling in April, which found that the rebellion charge could not be honored in Germany “because evidence of ‘violence’ is not present.” Violence is a component of the charge in Spain’s legal code.

Since then, however, Spain’s political landscape has changed considerably. A Socialist government took office in Madrid last month, led by Prime Minister Pedro Sánchez. His predecessor, Mariano Rajoy, had vehemently opposed Catalonia’s separatist movement, and moved to block an effort to re-elect Mr. Puigdemont as the region’s leader in May.

Mr. Sánchez said on Thursday that his government respected judicial decisions. And although he did not weigh in on whether extradition on the rebellion charge should also have been allowed, he said at a news conference that Spanish society “expected the people involved in the events of the second half of 2017 to be judged by Spanish courts.” He added: “This will happen.”

Writing on Twitter, Mr. Puigdemont welcomed the decision by the German court to strike down “the main lie of the state” by not recognizing the independence referendum as an act of rebellion.

And Quim Torra, who leads a separatist coalition that formed a new Catalan regional government in June, called the German ruling “great news.” He added: “Today the fictitious narrative of the Spanish state has fallen apart.”

On Monday, Mr. Torra visited Madrid to meet with Mr. Sánchez for the first time, an encounter that both men described as positive. The prime minister had previously vowed to “find a political solution to a political crisis” and return to the negotiating table.