The 27-year-old has been a long-term transfer target for Madrid and came close to moving to the Champions League holders in the summer of 2015.
De Geas current contract expires at the end of next season, although United have the option to extend that for a further year.
But Jose Mourinhos side have been in talks to significantly improve De Geas deal in light of the Spaniard establishing himself as arguably the worlds best goalkeeper.
De Gea, meanwhile, is adamant that he is happy to remain in Manchester.
Im always calm, De Gea said ahead of Spains clash with Switzerland on Sunday evening.
The important date is June 15.
The World Cup is important, for us to deliver a good performance, for the team to do well and for things to go as well as possible.
Personally, Im happy where Im at, happy and at the same time im focused on the national team.
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