Spain's Supreme Court reinstated arrest warrants for Catalonia's former leader and others accused of corruption in the region's failed independence push on Monday, ruling that a new amnesty statute does not apply to them.

The decision may destabilize Spain's shaky Socialist-led government and have personal consequences for ex-Catalan leader Carles Puigdemont, who lives in France in self-imposed exile.

Puigdemont's Junts party said that it would appeal and its secretary-general Jordi Turull, termed the ruling a "political decision that breaks the elemental norms of a democracy" and accused judges of staging a "coup" by attempting to take the legislative branch's role in torpedoing the law's implementation.

In late May, Spain's parliament on Thursday gave the final green light to a contentious amnesty bill for Catalan independentists, paving the way for the return of their figurehead Carles Puigdemont after years of self-exile.

Prime Minister Pedro Sanchez hailed the move, saying "forgiveness" was more powerful than holding a grudge over the 2017 crisis.

The investigating judge, Pablo Llarena, stated in his writ that he will continue to pursue the arrest of Puigdemont and his former deputies Toni Comin and Lluis Puig, who were in charge of Catalonia's health and cultural sectors.

A withdrawal of support from Junts for issues like the 2025 budget might render Sanchez unable to govern and force fresh elections.

The amnesty does not apply to people who committed embezzlement intending to personally benefit themselves or who harmed the European Union's financial interests.

Llarena contended that the accused actions of Puigdemont, Comin, and Puig "fully fit within the two exceptions contemplated in the law," citing they made personal gains by billing the costs of staging an unlawful independence referendum to the regional treasury, which he described as not in the public interest.

All three argue that the referendum was not unlawful, and so the claims against it have no validity.

Llarena also stated that the vote influenced the European Union's financial interests since Catalonia's separation would have harmed Spain's tax collection and gross national revenue.

Despite the Socialists preparing to take over the Catalan government, Puigdemont has expressed his desire to lead a minority pro-independence administration.

He has also expressed hope to return in time to witness the new Catalan government take office, which is scheduled to happen by June 25 at the latest.

However, it remains uncertain if this will be possible given the two-month period allocated for the courts to implement the legislation and cancel outstanding arrest warrants, including Puigdemont's.