Around 45,000 people took to the streets of Brussels in support of an independent Catalonia on Thursday, according to Belgian police.
With exactly two weeks until the upcoming Catalan elections, the region's main independence politicians also made appearances at the rally.
"Europe does not only have to listen to its states but also to its citizens," said Carles Puigdemont, the former Catalan president who fled to Brussels after declaring independence in the Catalan Parliament.
The presidents of the separatist groups that organized the rally, the National Catalan Assembly and Omnium Cultural, are both in prison. According to the organizations, they contracted 250 buses and five charter flights to bring separatists from Catalonia to Brussels.
From Spain, the rally was widely criticized by unionists.
"Having a Spanish ID and belonging to the European Union is what has allowed them to go there and protest," Soraya Saenz de Santamaria, deputy prime minister of Spain and current leader of Catalonia since Spain seized direct rule of the region, said in a news conference on Thursday.
If Catalonia were to become an independent country, EU rules say that it would automatically lose membership and need to reapply.
On Wednesday, a pro-unionist Catalan rally was also held in Brussels. According to organizers around 1,000 people showed up.
