Youths wrapped in a Catalan, a Spanish and an Estelada (Catalan separatist) flag walk through a street during a protest two days after the banned independence referendum in Barcelona, Spain, October 3, 2017. Picture taken October 3, 2017. REUTERS/Jon Nazca

MADRID (Reuters) - The influential Catalan business lobby Cercle d’Economia said on Wednesday it was extremely worried by the prospect of Catalonia declaring independence from Spain and called for leaders from both sides to start talks.

“Such a declaration would plunge the country into an extraordinarily complex situation with unknown, but very serious consequences,” the lobby said in a statement.

The lobby also condemned violence on Sunday, saying Catalan-Spanish relationships had deteriorated as a consequence, after Spanish riot police were seen beating Catalans attempting to cast a ballot in a vote the government had said was illegal.