Mr. Rajoy, whose remarks came after an emergency cabinet meeting earlier in the day about how to address the situation in Catalonia, addressed Spanish Parliament later in the day.
While Mr. Puigdemont is facing a fight for his own political survival — hard-line separatists have denounced his failure to deliver a clear message of independence — Mr. Rajoy appears to have consolidated his power base in Madrid, where he has been in charge of a minority government since late 2016.
Spain’s main opposition Socialist party expressed support for Mr. Rajoy as he discussed using Article 155, an idea it has been more reluctant to endorse in the past.
Pedro Sánchez, the Socialist leader, told a news conference that his party also supported Mr. Rajoy in his demands “to clarify and get out of the quagmire in which Mr. Puigdemont has put Catalan politics.”
In return, Mr. Sánchez said that he had reached an agreement with Mr. Rajoy to form a commission on changing the Constitution because “the Spain of 2017 is not the…