Spanish Prime Minister Mariano Rajoy has taken the first step towards suspending Catalonia's political autonomy and ruling the region directly to thwart a push for independence.
This requirement is a necessary step before triggering Article 155 of the constitution, which would allow Madrid to suspend the region's political autonomy.
Mr Rajoy's move could deepen the confrontation between Madrid and Catalonia but it also signals a way out of Spain's biggest political crisis since a failed military coup in 1981.
The Prime Minister would be likely to call a snap regional election after activating the constitutional mechanism allowing him to do so.
"The Cabinet has agreed this morning to formally request the Catalan Government to confirm whether it has declared the independence of Catalonia, regardless of the deliberate confusion created over its implementation," Mr Rajoy said after a Cabinet meeting to consider the Government's response.
Without giving a specific deadline for the Catalan Government to reply, Mr Rajoy said "the answer from the Catalan President will determine future events, in the next few days".
It is not yet clear if and when the Catalan Government would answer the requirement but it now faces a conundrum, political analysts say.
If Mr Puigdemont says he did declare independence, the Government would likely trigger Article 155. If he says he did not declare it, then far-left party CUP would likely withdraw its support to his minority government.
Mr Puigdemont had been widely expected to unilaterally declare Catalonia's independence on Tuesday after the Catalan Government said 90 per cent of Catalans had voted for a breakaway in an October 1 referendum that Spain had declared illegal and which most opponents of independence boycotted.
Madrid responded angrily to Mr Puigdemont's speech, saying the Catalan Government could not act on the results of the referendum.
"Neither Mr Puigdemont nor anyone else can claim, without returning to legality and democracy, to impose mediation... Dialogue between democrats takes place within the law," Deputy Prime Minister Soraya Saenz de Santamaria said.
Invoking Article 155 to ease Spain's worst political crisis in four decades would make prospects of a negotiated solution to the Catalonia crisis even more remote.
A spokesman for the Catalan Government said earlier on Wednesday that if Madrid went down this road, it would press ahead with independence.
"We have given up absolutely nothing... We have taken a time out... which doesn't mean a step backwards, or a renunciation or anything like that," Catalan Government spokesman Jordi Turull said.
Socialist opposition leader Pedro Sanchez said he would back Mr Rajoy if he had to activate Article 155 and said he had agreed with the Prime Minister to open a constitutional reform within six months to discuss how Catalonia could fit better in Spain.
It was not clear how the Catalan Government would respond to the offer.
Also known as the nuclear option, Article 155 of the Constitution, allows the central government to take some or total control of any of its 17 regions if they do not comply with their legal obligations.
This would begin with a Cabinet meeting and a warning to the regional government to fall into line.
Some 2.3 million Catalans — or 43 per cent of the electorate in the north-eastern region — voted in the referendum.
Regional authorities say 90 per cent were in favour and declared the results valid.
Those who opposed the referendum had said they would boycott the vote.
Mr Rajoy's Government had repeatedly refused to grant Catalonia permission to hold a referendum on the grounds that it was unconstitutional, since it would only poll a portion of Spain's 46 million residents.
Catalonia's separatist camp has grown in recent years, strengthened by Spain's recent economic crisis and by Madrid's rejection of attempts to increase self-rule in the region.
The political deadlock has plunged Spain into its deepest political crisis in more than four decades, since democratic rule was restored following the dictatorship of General Francisco Franco.