The lawmaker's party announced that they will appeal the decision.
Jailed Catalan leader Oriol Junqueras' mandate as a European Union (EU) lawmaker is over, the legislature's head said on Friday, in what could be showing support for the hardline followed by Madrid against the independentist movement.
European Parliament president David Sassoli said decisions this month by Spain's electoral board and Supreme Court blocking Junqueras from occupying his seat meant he had effectively no longer been a legislator for the bloc from Jan. 3.
Last December, Sassoli lifted a ban on entry into the European parliament of top Catalan leaders - the former president of the government of Catalonia Carles Puigdemont and the ex-minister of Health in the Catalan government Antoni “Toni” Comin.
Junqueras' Esquerra Republicana de Catalunya (ERC) party said it was "outraged" by the EU parliament's decision and would appeal. "We ... demand that ... the interests of a member state do not prevail over the interests of the union," it said.
Junqueras was sentenced to 13 years in prison in a controversial sentence in October over his role in Catalonia's failed bid for secession in 2017. He was elected an EU parliament member while in prison awaiting the verdict, but has not been able to take up his seat.
His case had got a boost last month after the EU's highest tribunal ruled Junqueras was entitled to immunity, but Spain's Supreme Court rejected that on Thursday.