Spain is considering constitutional changes that could allow its regions to hold referendums on independence in the future, the foreign minister says.
Alfonso Dastis has told the BBC a nationwide vote on the issue could be held.
The move is in recognition of the events in Catalonia, where the regional government was deposed after the unilateral declaration of independence.
Protests have been held against the detention of the region’s ex-leaders.
Eight politicians are being held in an investigation by Madrid authorities into alleged rebellion and sedition linked to the declaration of independence that followed a banned referendum.
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“We’ve 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,” Mr Dastis said.
“[But] a decision will have to be taken by all Spaniards.”
The Spanish government imposed direct rule over Catalonia after its declaration of independence and announced new elections for 21 December.
In a speech to parliament, Prime Minister Mariano Rajoy called for a big turnout in the vote so that Spain could get over the crisis.
He said sacked Catalan President Carles Puigdemont did not have the power to unilaterally declare the region’s independence from Spain.
“A regional leader cannot say the constitution doesn’t rule in his territory. A regional leader cannot invent a parallel legal framework.”
On Wednesday, protesters blocked all major roads and some railway stations across Catalonia against the detention of the separatist leaders. Minor scuffles were reported when police moved in to remove protesters.
But a call for a general strike was not backed by the region’s major unions, and shops and businesses appeared to be open as normal.
In other developments:
- Spain’s Environment Minister Isabel García Tejerina accused Mr Puigdemont of launching an attack on the entire Spanish state with his illegal declaration of independence
- Pro-independence parties failed to reach an agreement to form a united front for the snap election
- El Mundo (in Spanish) newspaper released a document which allegedly shows that Mr Puigdemont’s cabinet had several details ready for an independent Catalonia, including its budget, in June
- The editor of satirical magazine El Jueves has appeared in court over a satirical story (in Spanish) that suggested that riot police deployed to stop the referendum had finished the region’s supply of cocaine
Mr Puigdemont and four former advisers fled to Belgium after the Spanish government rejected the region’s independence referendum and imposed direct rule.
A Belgian investigating judge is yet to decide whether to execute an EU arrest warrant issued by a Spanish judge last week. The sacked leader has been freed on bail and is scheduled to appear in court on 17 November.
Meanwhile, Belgium’s Prime Minister, Charles Michel has denied his government is in crisis over Mr Puigdemont’s presence, an issue that risks exposing separatist divisions in the country.
He told parliament that the question over Mr Puigdemont was a “matter for the courts, not for the government”.