The Spanish government reacted swiftly to the Catalan regional parliament's declaration of independence on Friday.
Prime Minister Mariano Rajoy called a crisis cabinet meeting for Friday evening to enforce direct rule by Madrid on the secessionist region.
In Barcelona, the capital of the autonomous region, the local parliament voted for independence by 70 votes to 10 with two blank ballots, after pro-union opposition parties walked out before the ballot.
Thousands of people outside the parliament building cheered the vote.
In Madrid, soon after, the Spanish parliament's upper house voted for central government to take direct control of Catalonia and sack the region's president,Carles Puigdemont.
Senators voted by 214 in favour of the motion with 47 against and one abstention.
The measures are part of Article 155 of the Spanish constitution. It enables central government to stop any of the country's 17 regions to break away.
But, as Sarah Morris, RFI's Spain correspondent in Madrid explains, enforcing the takeover of Catalonia is a "difficult and delicate job".
Already pro-independence activists have urged civil servants and other public-sector workers to disobey Madrid's orders.
Yet one of Spain's biggest labour federations is advising its members, whether they are civil servants, health workers or teachers, to follow central government's Article 155 directives.
"The situation could play out in a very unpredictable way", Morris predicts.
Puigdemont challenges Rajoy
Until the end, she says, it was expected Puigdemont would step back from the brink. Only yesterday he was widely tipped to call for a regional election as a way out of the impasse.
But he seems to have "either lost his nerve or wobbled" under pressure from independence hardliners - two of his own MPs resigned and many threatened to brand him a traitor if he failed to call for a break from Madrid, she adds.
International reactions have so far been in support of Madrid.
US State Department spokeswoman Heather Nauert said in a statement that "Catalonia is an integral part of Spain and the United States supports the Spanish government's constitutional measures to keep Spain strong and united."
Earlier, European Council President Donald Tusk tweeted: "For EU nothing changes. Spain remains our only interlocutor. I hope the Spanish government favours force of argument, not argument of force."