Manchester United have told Real Madrid that David De Gea is not for sale at any price even though the keeper's contract at Old Trafford is set to expire in summer 2016, reports in Spain claim.

After reports in Spain last week revealed the United number one had already agreed personal terms to move to the La Liga giants, Louis van Gaal appeared to accept that De Gea's days in the Premier League are numbered and even confirmed the club have already drawn a list of alternatives to replace the Spaniard.

"He is Spanish and his girlfriend is Spanish and he can go to another great club, so it is difficult for him to decide. David De Gea shall not leave us so easily because we are a great club and he wants to participate. He is still behind Casillas but now a Spanish club is coming," van Gaal said after the game against Arsenal on Sunday 17 May, suggesting the keeper will leave the club.

Having only one year left on his contract at Old Trafford it looked like United were ready to negotiate his sale to Real Madrid at the end of the season rather than losing him for free as a free-agent the following summer.

But reliable Spanish radio station Cadena Cope claim that, after first talks between the clubs, United have surprisingly told Real Madrid that they are not likely to negotiate De Gea's departure at any price this summer – and are ready to keep him at Old Trafford until the end of his contract even though that will mean losing him for free the following year.

Cope claims that Real Madrid official believe that United's message is just a tactic to get as much as they can for the keeper – as even though he is close to the end of his contract Sir Alex Ferguson paid £18.9m to Atletico Madrid in summer 2011 when he was just a promising prospect.

But Cope assures that should United remain solid in their posture, Real Madrid may consider to press United by signing Bayer Leverkusen number one Bern Leno ahead of next season while signing De Gea as a free-agent in summer 2016.

Meanwhile, several reports in Spain claimed Real Madrid have already told Iker Casillas to stay at the club until the end of his contract in summer 2017 although he would be the second keeper should De Gea or any other stopper arrives this summer.