The Manchester United goalkeeper is understood to have attracted interest from Real Madrid in recent weeks, with the Spanish giants keen to recruit a long-term replacement for Iker Casillas.
De Gea has been heavily linked with a move to the Bernabeu in recent weeks as the speculation surrounding his future continues.
Speaking after Manchester United’s 1-1 draw with Arsenal at Old Trafford on Sunday, Van Gaal suggested that De Gea is facing a tough decision in the coming weeks.
De Gea told BBC Sport after Sunday’s game: “The same thing as I have always said. It is a process for David De Gea.
“He will not leave us easily as we have a great club and he wants to participate. But he is Spanish. And he could go to a great club. It is difficult for him to decide.”
The Red Devils took the lead against Arsenal in the 30th minute at Old Trafford when Ander Herrera drilled home from close range.
United dominated proceedings in the first half but Arsenal improved after the break and the north London side equalised in the 82nd minute when substitute Theo Walcott’s cross was deflected in by Tyler Blackett.
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