(FILES) This file photo taken on September 11, 2016 shows people waving 'Esteladas' (pro-independence Catalan flags) as they gather during a pro-independence demonstration, in Barcelona during the National Day of Catalonia 'Diada'. The president of Spain's Catalonia region vowed on September 09, 2017 to press ahead with an independence referendum, that Madrid insists would be illegal, calling for mass demonstrations next week in support of a split. After sparking Spain's deepest political crisis in 40 years this week by voting to push ahead with the referendum, Catalonia's separatist-controlled regional parliament upped the ante by passing a bill early on September 8, 2010 outlining a transition to a possible independent republic. / AFP PHOTO / PAU BARRENA