madrid spanish government could use constitutional power suspend catalonia autonomy prevent region split spain prime minister mariano rajoy say interview newspaper el pais publish late saturday ask ready trigger article 155 constitution enable sack regional government call fresh local election rajoy answer rule absolutely anything within law ... ideally necessary implement extreme solutions happen things would change rajoy also say plan leave catalonia extra 4,000 police officer government ship region independence vote oct. crisis conservative prime minister add would call snap national election result political crisis rule use mediation resolve spain 's pm say could use constitutional power stop catalan independence