If Catalan authorities decide to declare independence from Spain following the results of the referendum, they will hardly be able to enjoy their status as the tensions with Madrid over violation of the Spanish constitution will rise and there will be no support internationally since other states would not sacrifice their relations with Spain for Catalonia's sake, experts told Sputnik.
Thousands of people gathered Saturday in Madrid to defend the unity of Spain, the Constitution and the rule of law in the face of an independence challenge and a possibility of an imminent unilateral declaration of independence in Catalonia.
Asked if he was ready to trigger article 155, Mr Rajoy told El Pais newspaper: "I don't rule out anything that is within the law".
The Spanish official added that the Catalan movement aimed at obtaining more autonomy for the region should be peaceful and be conducted "within the framework of treaties".
People take part in a demonstration in favour of dialogue to resolve Catalonia´s bid for independence, in Madrid, Spain, October 7, 2017.
Other protests asking for dialogue were held in cities including Valencia, Bilbao, Pamplona and Sanitago de Compostela, news agency Europa Press reported. "Because (Catalonia) is going to lose more than (Spain) because businesses are fleeing from here already", said protester Juliana Prats, a Barcelona resident.
The demonstrations were in response to last Sunday's disputed referendum on Catalan independence.
Spain's red-and-yellow flag has always been taboo here in Catalonia and throughout the country because it has been linked to groups supportive of Gen. Francisco Franco's dictatorship.
The turnout was just 43 percent of eligible voters as Catalans who prefer to remain in Spain largely boycotted the polls. Madrid responded to the vote with force, sending thousands of police to the region to shut down the vote.
Weekend looking nice, and then we'll get some much-needed rain
Monday will be likely be a washout with a much-needed, soaking rainfall-which could be heavy at times Monday night . A warm front moves through Saturday with more clouds and just a slight chance of a shower, mostly in northern NH.
"I live in Catalonia, I speak Catalan, and I am Spanish", she said.
Raul del Hoyo, 56, a logistics technician, said he feels Spanish as well as Catalan but believes in the region's bid for independence. "I think a couple of years ago there were more people who didn't want it (independence), but after all that has happened, I think there are more people who want it".
Spain's sharp economic downturn also helped push the independence cause from the fringes to the mainstream by fueling a sense that Catalonia would be richer on its own.
Catalan President Carles Puigdemont is expected to address the regional parliament on Tuesday at 18:00 local time (16:00 GMT) after Spain's Constitutional Court earlier suspended the Catalan parliament session that had been planned for Monday.
He did not rule out suspending Catalonia's regional autonomy - a move that could risk sparking unrest.
But Sunday marks the second consecutive day of protests in Spain, with thousands marching on Saturday, calling for dialogue to defuse the tense situation.
"I can do nothing but regret it, apologise on behalf of the officers who intervened", said the government's representative in Catalonia, Enric Millo.
"We want Barcelona to once again be the capital of Spanish culture".