During an interview on Tuesday morning, after several hundred thousand Catalan separatists congregated in central Barcelona on Monday, the First Minister, Carles Puigdemont, said the main role of police officers was to ensure citizens' safety.

"There will be 6,000 ballot boxes around [Catalonia], and between choosing to remove ballot boxes or looking after people's safety, I think the police, all of them, have priorities in life; removing a ballot box is not investigating crime, organising a referendum is not a crime."

"A ballot box is not criminal material", he continued: "a ballot paper is not criminal material, a politician who organises a referendum is not a delinquent".

Last week, the public prosecutor's office filed criminal charges against Mr. Puigdemont and all of his regional government ministers for contempt, abuse of authority and misuse of public funds.

"As far as the Catalan government goes, yes, I guarantee the referendum", he said.

The Constitutional Court is meeting again on Tuesday to deal with the Catalan question again, and is likely to issue further suspensions and warnings.

"If the Constitutional Court suspends me", said the First Minister: "I will go to work the day afterwards all the same".

The Catalan government's attitude, combined with the criminal investigation, mean the Catalan police—the Mossos—will be right in the middle of the conflict if it continues all the way until October 1.

Catalan police chief Josep Lluís Trapero has been called to a meeting at the public prosecutor's office on Tuesday to discuss the arrangements.

If the Catalan government ordered the ballot boxes deployed for October 1, and the central government or judges ordered them removed, there are doubts about what the Catalan police, or some of its officers, might do.

Last Thursday, a spokesman for one of the leading Mossos trade unions, Antoni Castejón, told a radio programme that officers would follow the law: "a judge's word is law".

At a breakfast speech in Barcelona on Tuesday, Socialist Party (PSOE) leader Pedro Sánchez said he would be prepared to devolve even more powers to the Catalan regional government as part of a deal to "find a new political way to fit Catalonia into Spain".

Central government spokesman Iñigo Méndez de Vigo said on Tuesday morning that if he wants to call a vote, Mr. Puigdemont should "call early regional elections".

"That is within his power and ability" whereas the Catalan government may not, under Spanish law, call a referendum on secession.