According to Alejandro Alcazar of Sport, the United No. 1 is still high on Real president Florentino Perez's wanted list, but Los Blancos are unprepared to meet the Red Devils' asking price and they will wait in the hope De Gea does not sign a new contract before 2019 and becomes available for free.
Until then, Real are happy with Keylor Navas as their first-choice stopper, although Chelsea's Thibaut Courtois remains a potential target, added Alcazar.
De Gea, 27, was minutes away from signing for Real for £29 million back in 2015, but the deal collapsed due to late submission of paperwork, per Simon Stone of BBC Sport.
After the failed move, the Spanish goalkeeper signed a new four-year contract to 2019 at Old Trafford, and there remains the option for him to extend a year further.
It is little surprise Real have maintained their interest in De Gea ever since, as he has only enhanced his reputation with consistently stunning performances and is now arguably the best goalkeeper on the planet.
The 2017-18 campaign has seen De Gea continue to impress in between the posts, per Squawka:
Squawka Football @Squawka
Manchester United are now the first team to keep 15 clean sheets in the Premier League this season. David de Gea in goal for all 15 of those games. https://t.co/OfMkVBWuAe2018-2-3 17:32:07
Given his status as one of Europe's top 'keepers, he deserves the price tag United have reportedly placed on him as he is indispensable to Jose Mourinho's side.
The world-record fee paid for a goalkeeper is different depending on currency. It either remains the €53 million (£32.6 million) Juventus paid Parma for Gianluigi Buffon back in 2001, or it was eclipsed by Manchester City's €40 million (£35 million) outlay for Ederson last summer, per BBC Sport.
Either way, United are demanding Real obliterate the record to sign De Gea but, given how the market has changed since Paris Saint-Germain's £200 million signing of Neymar, that is arguably a reasonable request.
B/R Football @brfootball
David De Gea was simply incredible today 🚫 https://t.co/qxJukUbgwb2017-12-2 20:05:20
As such, United likely see him as similarly valuable to a goalscoring attacker.
They will be eager to ward off renewed interest in De Gea from Real and have seemingly given the Madrid giants pause for thought with their valuation of the Spain international.