SPAIN’S foreign minister signalled a concession yesterday to Catalan separatists as a pro-independence union staged a general strike in the region.

Alfonso Dastis told the BBC that Prime Minister Mariano Rajoy’s government was considering changing the constitution to permit currently-banned regional independence referendums.

“We have created a committee in parliament to explore the possibility of amending the constitution to be able to accommodate better the aspirations of some of the Catalan people,” he said.

The government cracked down hard on last month’s independence referendum in the autonomous community, with police shipped in by Madrid hurting 1,000 people.

Despite police attempts to stop the poll, there was 92 per cent support for independence on a 43 per cent turnout.

Mr Dastis said the police violence was acceptable.

Meanwhile the small pro-independence Intersindical CSC union federation staged a strike and roadblocks — ostensibly over labour rights but coinciding with protests for independence campaigners Jordi Cuixart ands Jordi Sanchez.

Spain’s Constitutional Court unsurprisingly ruled yesterday that the now-dissolved Catalan parliament’s declaration of independence was invalid.

Nine regional ministers including vice-president Oriol Junqueras were remanded last week on charges of rebellion and misuse of public funds for the referendum.

Sacked president Carles Puigdemont’s lawyer Alonso Cuevillas has alleged some were badly mistreated after they were arrested on Thursday, including two being strip searched on Saturday.

Relatives of one said that when they were moved in a prison van “it was quite brutal because they handcuffed them from behind and there was no seatbelt. The van was going very fast, so they were very bruised by the time they got to the jail.”

Guards played the Spanish national anthem on a loop and a video posted online showed national police insulting them men and making homophobic comments as they arrived in court.