Authorities in Finland have received a Spanish request to arrest separatist Catalan leader Carles Puigdemont.

The arrest warrant was issued on Friday, a day after his arrival there.

The ex-leader has been living in self-imposed exile in Belgium since last October’s banned referendum that backed Catalonia’s unilateral secession bid.

Tensions in the region are very high and separatist leaders have abandoned plans to name a new president following the arrest of the latest candidate.

Crowds of protesters clashed with police in Catalonia on Friday night after Spain’s Supreme Court ruled 25 Catalan leaders should be tried for rebellion, embezzlement or disobeying the state.

Convictions could result in up to 30 years in prison.

One of those taken into custody was Jordi Turull, who was to be the subject of a vote in the Catalan parliament on Saturday for regional president.

Other separatist figures were already in custody or had gone into exile abroad.

Mr Puigdemont has been in Finland since Thursday.

His lawyer, Jaume Alonso Cuevillas, told Catalunya radio on Saturday that Mr Puigdemont would co-operate with the Finnish authorities. His client “had not fled from Spanish justice”, he said.

Friday’s rulings at the Supreme Court in Madrid were considered the most serious challenge to date to the Catalan independence movement. Almost the entire leadership now faces a major legal fight.

Altogether 25 separatists have been charged variously with sedition, rebellion, embezzlement and other crimes. They deny the allegations.

The five Catalan politicians remanded in custody on Friday were:

• Jordi Turull – former Catalan government spokesman and the latest candidate for regional president
• Josep Rull – former Catalan development minister
• Carme Forcadell – former Catalan parliament speaker
• Raul Romeva – former Catalan foreign affairs chief
• Dolors Bassa – former Catalan labour minister

All five spent some time in detention following the banned referendum but were released on bail late last year pending investigations into their individual roles in the vote.

In his 70-page ruling, Supreme Court Judge Pablo Llarena said that they should be returned to jail as they represented a flight risk. He did not set a date for their trial.

The five join four other Catalan leaders already in prison. They include Oriol Junqueras, the former Catalan vice-president, and Jordi Sánchez, who was nominated to lead the Catalan government but dropped the bid after the Spanish authorities refused to release him to attend an investiture ceremony.

Judge Llarena also issued an arrest warrant for Marta Rovira, the deputy head of the separatist Esquerra Republicana party, who failed to appear in court on Friday.

It later emerged that she had fled into exile and Spanish media reported that she was in Switzerland.

Following the referendum, the central government in Madrid sacked the Catalan regional government, imposed direct rule and called new elections but pro-independence parties returned with a slim majority.

In a setback for the pro-independence cause, a survey published by the Catalan Centre for Opinion Studies recently suggested support for independence had dropped sharply, with 53.9% of Catalans now against the idea and 40.8% saying they were in favour.

Mr Puigdemont, himself, recently said a majority of Catalans might support Swiss-style federal autonomy, rather than full independence.