Mbappe has caught the eye with a series of impressive displays in Ligue 1.
The 18-year-old has struck 19 goals from 32 games for Monaco this season.
Kylian Mbappe is wanted by Real Madrid
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Kylian Mbappe is currently on international duty with France
Reports in Spain yesterday suggested that United were ready to directly challenge Madrid for his signing.
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And Real chief Perez has refused to rule out a summer move.
“Everything is possible, but at this time of the season, I don't want to talk about that”, he told French radio station RMC.
Cristiano Ronaldo wants Kylian Mbappe to join him at Real Madrid
Madrid could move for the striker to keep Cristiano Ronaldo happy.
It was reported yesterday that the forward had approved a proposed bid to sign Mbappe at the end of the season.
He believes the Monaco star has the potential to be world-class and has banned the signings of Robert Lewandowski and Pierre-Emerick Aubameyang as a result.