Real Madrid manager Zinedine Zidane has insisted that he is not interested in mounting speculation that midfielder Isco is holding out for a move to arch rivals Barcelona.

The 24-year-old, in and out of Los Blancos' staring lineup this season, was forced to explain on Thursday why he was pictured with a packet of Barcelona-branded potato chips.

Isco has admitted in the past to being frustrated by a lack of regular minutes at the Bernabeu, but recently stressed that he was not angling for a move to Camp Nou when his contract expires next year.

Zidane is also unconcerned by the speculation, which is unlikely to end unless the Spaniard puts pen to paper on a new deal, insisting that it is just "part of football".

"There's no controversy about the potato chips, we are just thinking about the game tomorrow," Zidane told reporters on the eve of his side's La Liga showdown with rivals Atletico Madrid.

"We know that all of this [speculation] is part of football - everything that's said and written off the pitch. We are only interested in what's going on on the pitch and what we're going to do."

Isco has seven goals in 24 La Liga appearances this season, while also registering five assists.