Catalan separatist leader Carles Puigdemont is to unveil Thursday his plans for Catalonia's snap May election, a move that could bring forward his return home after years of self-imposed exile.

A European Parliament lawmaker who fled Spain for Belgium to avoid prosecution over the botched 2017 Catalan independence bid, Puigdemont plans to announce whether he will stand as a candidate at a 7:00 pm (1800 GMT) press conference in southern France.

"We went into exile for the same reasons that we will return, the future of our nation," Puigdemont, who was Catalan regional leader at the time of the secession bid, wrote on X.

Last week, Pere Aragones, the current leader, called a May 12 snap election in the wealthy northeastern region, on the eve of a key parliamentary vote in which Spanish lawmakers approved an amnesty law for Catalan separatists.

The bill, which aims to draw a line under years of efforts to prosecute those linked to the independence bid, is currently before the Senate but will return to the lower house for a final green light in around two months.

At the time, a smiling Puigdemont, 61, had told reporters it could mean he would be back in Spain to welcome the new Catalan leader into office.

But members of his hardline separatist JxCat party did little to hide their enthusiasm to see him run in the high-stakes election, even if he would not be back in time to campaign in person.

"With the amnesty bill, his outlook is no longer exile but return," JxCat's secretary general Jordi Turull told El Pais newspaper.

Named Catalan leader in 2016, Puigdemont led the independence bid the following year that sparked Spain's worst political crisis in decades before fleeing to Brussels, where he was elected a eurodeputy in 2019.

Separatists divided

With the Catalan separatist movement in the doldrums, the outcome of Spain's inconclusive July election was a gift for Puigdemont, whose party was cast in the role of kingmaker.

After months of political uncertainty, JxCat's seven lawmakers decided to back Prime Minister Pedro Sanchez, its votes enabling him to secure a new four-year term in November.

In exchange, the party demanded the amnesty bill, which will affect around 400 people, first and foremost Puigdemont.

Although rejected in late January after JxCat voted against it on the ground it did not go far enough, the bill passed on March 14 with fresh wording the party sees as sufficient to avoid prosecution for terrorism or treason.

In late February, the Supreme Court opened an inquiry into Puigdemont on "terrorism" charges over his alleged links to mass protests by a group called Democratic Tsunami.

Even when the law comes into force, there is no guarantee Puigdemont will not be arrested on return to Spain, his lawyer Gonzalo Boye told Catalonia's RAC1 radio station, saying however he would "accept the consequences of his decisions".

'Look ahead'

Polls suggest the vote in Catalonia, which is home to eight million people, will be tight.

A survey published Thursday by Catalonia's regional-run polling firm CEO put the Catalan branch of Spain's governing Socialist party in the lead with 25-29 percent support, followed by the moderate separatist party ERC at 17-20 percent, and JxCat with 15-18 percent.

Initially, the two separatist parties had ruled Catalonia in coalition following the 2021 elections, but JxCat pulled out of Aragones's ERC-led government in 2022, exacerbating divisions within the movement.

Although Aragones, who will run again as ERC's candidate, expressed a desire to see Puigdemont return and participate in the campaign, he said he thought the JxCat leader's time was over.

"I respect him for what he's achieved in his career but I think that Catalonia needs to look ahead," he told La Vanguardia newspaper on Sunday.