Spain lurched further towards a constitutional crisis as Catalonia announced a snap election potentially opening the way for the country’s most economically important region to declare independence from Madrid.

As police in the Spanish capital barricaded parliament against anti-austerity protesters, the government of Mariano Rajoy vowed to stand firm over Catalonia’s drive for secession, which comes at a critical time for the Spanish leader.

“The hour has come to exercise our right to self rule,” said Artur Mas, Catalonia’s president. He called the vote, which is likely to be cast as a proxy referendum on Catalan independence, after Mr Rajoy last week rejected his demands for greater fiscal autonomy, triggering nationalist sentiment in the northern region.