CATALAN government ministers sacked for their part in the October independence referendum start work this week as a “government in exile” from a building in the Belgian town of Waterloo which they have christened the House of the Republic.

Carles Puigdemont, the sacked president, has returned to Belgium from Germany after Spain’s bid to extradite him on rebellion charges failed.

Hundreds of supporters gathered in Waterloo to welcome him as he met the current Catalan president Quim Torra and Clara Ponsati, his former education minister and St Andrews University professor, who was free to travel from Scotland after Spain withdrew a European Arrest Warrant against her.

Although the gathering saw a restatement of Puigdemont’s vision for an independent Catalonia, it was also an expression of support for the nine pro-independence figures, some of whom have been in jail for more than nine months.

Speaking from a balcony of the House of the Republic, he called for their immediate release: “The political prisoners should not spend a single minute in jail.

“There is no justification for spending a minute more in prison.

“The freedom we yearn for, for which we are fighting, begins to demand the freedom of our imprisoned companions.

“It is an inexcusable duty. It is not a matter of how long, short, easy, or complex the path, but there is a path and it has a good end.”

Standing alongside him, Torra said the trial against the jailed pro-independence leaders was “a farce,” as demonstrated by the freedom of the exiles.

He said: “On October 1 we voted, on October 27 we politically declared independence and what is happening now to the government and the Catalans is to make this mandate effective.

“The cause of independence is fair. It is an honourable fight. Know that we are on the right side of the story.

“We are fighting for freedom, for justice, for democracy, for human rights.

“The cause of independence is a just cause. We have seen that in Europe, in a free Europe that judges freely and where there is a separation of powers, today our exiles are all here.”

Torra urged Catalans: “Fight peacefully against the shame and the indecency of a state that sends the police against the citizens, against a state capable of imprisoning decent politicians who did what we asked for them.

“And against a state that has opened a judicial cause that is a farce.

“This repression must end immediately, and all charges must be dropped by the Spanish prosecutor.”

Anna Forn, the daughter of Joaquim Forn, the former vice-president who has withdrawn from politics but who remains in prison, read a statement from those still locked up.

“We are proud and strongly committed to the cause of the republic, very soon to be in Catalonia,” they wrote.

Mallorcan rapper Valtonyc, who had also fled to Belgium to avoid a prison sentence over some of his lyrics, described Spain as a “dictatorship”.

He added: “Today, I am the exiled, but tomorrow it could be you, a brother, a son, or a friend.”