The centre-back insists he is focused on Brazil's friendly clash with Switzerland amid interest from the Catalan giants and would take no questions on his future
The Camp Nou club are poised to make a second bid for the centre-back after having an initial €25 million move rejected.
Luiz is currently away with the the Brazilian national side as they prepare for a friendly fixture with Switzerland in Basel.
But the 26-year-old is not answering questions on his club career, preferring to focus instead on Wednesday's game at St Jakob-Park.
"I will only talk about the national team because this is all I can think about when I come here, that's how I think," Luiz is quoted as saying by Globo Esporte.
"It was like this in Brazil during the Confederations Cup, and it will be like this here.
"You (the media) can try everything, but you won't get anything from me."