Definition: Given a document, generate a short title of the document. The title should convey the main idea/event/topic about which the document is being written. Note that URLs in the text have been replaced with [Link].
Input: Spanish Prime Minister Mariano Rajoy  vows that  his  government will not allow Catalonia  which represents a fifth of Spain's economy  to break away from the rest of the country.
In an interview with the Spanish newspaper El Pais published Sunday   Rajoy  said that  he  will consider employing any measure "allowed by the law" to stop the region's separatists.
 Rajoy  said that includes the application of Article 155 of the Spanish Constitution  which would allow the central government to take control of the governance of a region "if the regional government does not comply with the obligations of the Constitution."
"The ideal situation would be that I don't have to find drastic solutions  but for that to happen there will have to be some rectifications (by Catalan leaders) "  Rajoy  said.
Rallies were held Saturday in Madrid  Barcelona and other cities to demand that  Rajoy  and Puigdemont negotiate to find a solution to Spain's worst political crisis in nearly four decades.

Hundreds of thousands rally against Catalonia secession