Puigdemont flew to Brussels earlier this week with a handful of his deposed ministers after Spanish authorities removed him and his cabinet from office for pushing ahead with the declaration despite repeated warnings that it was illegal.
Puigdemont’s Belgian lawyer has already said his client will fight extradition without seeking political asylum.
Puigdemont was summoned to appear at Spain’s national court on Thursday to give evidence relating to possible charges of sedition, rebellion and misuse of public funds, but failed to appear. He has said he would only return to Spain if he were offered guarantees that the judicial process he would face were fair.
Late on Friday, Puigdemont told the Belgian public TV channel RTBF that he would put his faith in the Belgian courts.
He said: “I will not flee from justice. I will go towards justice, but real justice. I’ve told my lawyers to tell the Belgian justice system that I’m completely available to cooperate.
“It’s obvious it’s politicised. The guarantees are not there for a fair, independent trial.”
It was Puigdemont first interview since arriving in Brussels on Monday and it he claimed there was “enormous influence of politics over the judiciary in Spain”.
He said: “It’s not normal that we risk 30 years in prison, it’s extremely barbaric, we can not talk about democracy.”
Puigdemont said he was ready to stand in the election, adding: “It’s possible to run a campaign from anywhere. We consider ourselves a legitimate government.
“There must be a continuity to tell the world what’s going on in Spain … It’s not with a government in jail that the elections will be neutral, independent, normal.”
In a written request to the judge, prosecutors said Puigdemont and four other members of his administration were aware they had been ordered to testify, but had chosen not to attend.
Of the nine former ministers who did appear in court in Madrid on Thursday, eight were remanded in custody.
A ninth Catalan minister, Santi Vila, was released from custody on Friday after posting bail of €50,000 (£44,000). Vila, who resigned from Puigdemont’s government a day before the independence declaration, said as he left prison near Madrid: “I ask for all political parties across to Spain, appealing to their democratic values, to put an end this terrible situation that has put politicians in prison.”
The Spanish government insisted that the jailings were not politically motivated. The education minister, Íñigo Méndez de Vigo, said the matter had been decided by a judge and the government was instead focusing on elections called by the prime minister, Mariano Rajoy, for December.
“There is a separation of powers in Spain and what happened yesterday is in the realm of the justice system and beyond the reach of the government,” Méndez de Vigo said on Friday.
“What the government guarantees is that there will be elections where the parties which want to run can present their programmes, and we hope that the election can end this period of uncertainty and the deterioration of harmonious coexistence in Catalonia.”
Lawyers for those under investigation said their clients would appeal against the judge’s decision, which they described as unjustified, disproportionate and predetermined.
In a televised address on Thursday evening, Puigdemont had branded the detention of his colleagues a “very serious attack on democracy” and called for their immediate release. Speaking as thousands of people protested across Catalonia, he said: “Imprisoning political leaders for fulfilling an electoral commitment breaks down the basic principles of democracy.”
On Friday, judges at the national court refused an appeal to release two grassroots pro-independence leaders who were remanded in custody last month as part of a separate investigation into alleged sedition. The jailing of Jordi Sánchez, the president of the Catalan National Assembly (ANC), and Jordi Cuixart, the president of Òmnium Cultural, brought hundreds of thousands of Catalans out on to the streets in protest.
A parallel supreme court session for six parliamentary officials, including Carme Forcadell, the speaker of the regional parliament, was postponed until next week following a request from their lawyers.
Spain has been convulsed by crisis since Puigdemont’s government held a unilateral independence referendum in defiance of Spain’s government, constitution and constitutional court on 1 October.
Minutes after a vote in the Catalan parliament – boycotted by opposition MPs – in favour of independence last Friday, the Spanish senate granted the government in Madrid unprecedented powers to impose direct rule on Catalonia under article 155 of the constitution.
Rajoy used the article to sack Puigdemont and his government and announce snap regional elections on 21 December.
A previous commitment to accept the election results had allayed fears that secessionists might boycott the ballot in the hope of denying it legitimacy.
Jean-Claude Juncker, the president of the European commission, will travel to Spain on Thursday to receive an honorary degree from the University of Salamanca. A spokeswoman for the commission was unable to provide any further details on his agenda during his visit.
Juncker has previously offered his support for Rajoy, while publicly complaining that Madrid has failed to take his advice on avoiding a crisis in Catalonia.
Responding to questions from reporters about the validity of the international arrest warrant, given its political dimension, Junker’s spokeswoman refused to be drawn. “This is a matter entirely for the judicial authorities whose independence we respect fully,” she said.
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