Madrid are reportedly making moves to bring De Gea to the Spanish capital in the summer.
Spanish outlet Marca claim the La Liga club could make a £55million move for the striker at the end of the season.
But De Gea has now insisted he is happy at Manchester United.
David De Gea is happy at Manchester United despite speculation linking him with Real Madrid
Manchester United star David De Gea
I will not talk about that [Real Madrid]
"The future no one knows," De Gea told Spanish outlet AS.
"The future is the future.
"I'm very happy here, it's a great club.
Man United stars snapped arriving at Carrington as Watford preparations continue
Thu, February 9, 2017
Manchester United players arrive for training… but one player doesn't want to be seen!
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Jose Mourinho didn't look too excited as he was driven to Carrington
David De Gea is under contract at Manchester United until 2019
"In England football is much enjoyed.
"I will not talk about that [Real Madrid].
"I will not talk about it anymore. Now I have to stay focused with my club."
De Gea is under contract at United until 2019, and the Red Devils have the option of extending his deal for a further season.