Former Catalan leader Carles Puigdemont has made a renewed call for Spanish authorities to open negotiations over Catalonia's secession claim, a day after he was released from a German prison.

Mr Puigdemont told reporters that he hoped a German court's decision not to extradite him to Spain on charges of rebellion shows that "dialogue is needed" to defuse the political conflict in his home country.

"I hope the situation could help ... Spanish authorities understand that political measures are needed," Mr Puigdemont said at a press conference in Berlin.

"This opens a new opportunity of dialogue."

The former leader left a German prison in Neumuenster on bail on Friday, almost two weeks after his arrest, after the Schwesig state court in Germany decided the charge of rebellion did not warrant extradition.

Mr Puigdemont can still be extradited on the less serious charge of misuse of funds to hold Catalonia's banned independence referendum last year.

Germany Justice Minister Katarina Barley applauded the court's decision to free Puigdemont on bail.

Katarina Barley told daily Sueddeutsche the judges' decision was "absolutely right" and what she had expected.

Ms Barley said it was now up to Spain to prove their other charges against Mr Puigdemont, which she said "won't be easy".

Misuse of public funds carries a sentence of up to eight years in Spain, while a rebellion sentence can reach 30 years.

Mr Puigdemont told reporters he would stay in Berlin at a location that he has yet to determine until his extradition case is concluded.

If he is not sent back to Spain, he said he would plan to return to Belgium where he has established residency in Waterloo since fleeing there from Spain in October.

The former Catalan leader was detained on a European arrest warrant after entering Germany on March 25.

He was trying to drive from Finland to Belgium, where he had been living since fleeing to escape arrest in Spain.