The Catalan government on Monday faced a set back to its attempt to fast track certain bills needed to hold the planned independence referendum on October 1, as Spain's Constitutional court accepted the government's challenge.
On Friday the central government filed an appeal against the Catalan government's approving of the fast track scheme.
"By presenting this appeal the government is fulfilling its duty to make sure the law is upheld," the Prime Minister Mariano Rajoy told a news conference.
"Catalan society needs to be protected from a radical and divisive project which is being imposed on them by force," he added.
"There will not be any referendum on October 1st. This is not constitutional and it is not legal."
Catalan politicians remain defiant however, with the regional president, Carles Puigdemont saying he is ready to go to prison for independence.