"If there were to be a declaration of independence, it would be unilateral, and it would not be recognised," Ms Loiseau said on CNews television.
Catalonia, which has its own language and culture and is led by a pro-independence regional government, held a referendum on October 1 over secession in defiance of Spain's constitutional court, which had declared the vote illegal.
"Catalonia cannot be defined by the vote organised by the independence movement just over a week ago," the French junior minister said. "This crisis needs to be resolved through dialogue at all levels of Spanish politics."
"If independence were to be recognised - which is not something that's being discussed - the most immediate consequence would be that (Catalonia) automatically left the European Union."
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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