The Constitutional Court ruled on Tuesday that an amnesty law for Catalan separatists applies to embezzlement charges against Puigdemont. Shortly afterwards, the Supreme Court responded by lifting a warrant for Puigdemont's arrest.
The likely homecoming of the former Catalan head of government could further unsettle an already volatile political landscape ahead of the election. Puigdemont fled to Belgium in 2017 after holding an independence referendum for his region that Madrid had declared illegal.
In a televised address from his home in the Belgian town of Waterloo, Puigdemont hailed the court rulings as a victory that "obliges us to put an end to political repression", but gave no indication of when he plans to return.
Prime Minister Pedro Sanchez had enacted the amnesty under a 2023 agreement between his Socialist Party and two Catalan parties, including Puigdemont's Junts, in exchange for their support for him to remain prime minister. The move triggered intense social and political opposition from the government's critics at the time.
The Supreme Court had initially ruled that the amnesty did not apply to the crime of embezzlement, which meant Puigdemont and others could still be arrested on charges of embezzling the funds spent on the referendum.
But the Constitutional Court, which has a progressive-leaning majority, ruled in an appeal that disallowing the amnesty for embezzlement unconnected with private enrichment would violate the purpose of the amnesty law.
A year ago, Junts withdrew its support for the minority central government. Unable to pass laws, Sanchez called the snap election on Monday. Sanchez told reporters on Tuesday he did not regret launching the amnesty, and welcomed the court ruling.
"I believe the important message is that of coexistence among Catalans," he said.
Although separatism has lost ground and Junts is trailing in opinion polls, Puigdemont's return could spark fresh political drama.
Spain's conservative People's Party is leading in opinion polls ahead of the election and may need to seek the support of Junts and other centre-right parties to govern.
Catalonia unilaterally declared independence from Spain in 2017 after the referendum. Although some 90 per cent of voters backed independence, Catalans who wanted to remain part of Spain mostly boycotted the ballot and many polling stations were shut.
Puigdemont then fled the country, while several of his former ministers stayed and were jailed until later being pardoned by Sanchez.
