Both vowed to use their new status to push the secessionist cause on Europe's agenda. Their parliamentary position also gives them immunity.

Puigdemont was at the forefront of the illegal referendum campaign in Catalonia in 2017 but he managed to flee to Brussels when Spanish authorities issued an arrest warrant for him.

'Free Junqueras'

The fugitive leader used the opening session of the plenary in Strasbourg to demand the immediate release from a Spanish jail of another Catalan official who was elected to the European Parliament, former Catalonia vice president Oriol Junqueras.

He waved a yellow poster demanding ''Free Junqueras.''

In October, a Spanish court sentenced Junqueras to 13 years in prison for sedition.

Puigdemont arrived at the legislature in the early afternoon, cheered by a few hundred supporters who had over a dozen Catalan flags fluttering in the midday winds outside the legislature in northeastern France. ''Puigdemont president,'' they shouted in unison.

Puigdemont and Comin, who are both wanted in Spain for their role in the 2017 secession bid, were only able to take up their seats in the European Parliament after the EU's top court ruled that they could.

But the ruling didn't solve the case of Junqueras. The European Parliament followed a Spanish Supreme Court decision and removed Junqueras' mandate, leaving him in jail.

“If the European Union was really a union of rights and freedoms, Oriol Junqueras would be here today,” Puigdemont said on Monday.

Spain’s top Court called on Friday for the European Parliament to strip Puigdemont and Comin of their immunity based on their European arrest warrants.

Immunity vote looms

Puigdemont said he was looking for a vote from the European Parliament ''within weeks'' over whether he can visit Spain without being arrested. He specifically wants to visit Junqueras.

“We hope, in a few, not too (many) months, probably weeks, we have a clear statement from the board of the European parliament,“ he told AP news agency.

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