Los Blancos have been long-time admirers of the young Frenchman, who burst into worldwide attention at the 2018 World Cup.
By that point he had already become the most expensive teenager in history when he joined PSG from Monaco the summer before.
He has since become one of the Ligue 1 side’s most important players, scoring 132 goals in 171 games in all competitions for the Parc Des Princes side.
But despite winning 10 trophies in four years with the French giants, Mbappe is so far refusing to sign a new contract.
The 22-year-old’s current deal expires at the end of next June, but PSG are struggling to convince him to stay in the French capital.
Real Madrid and Liverpool have both been linked with moves for the superstar, with the Spanish giants long believed to be his next destination.
One man he could ask about what it is like playing in La Liga is Ramos, who recently made the opposite journey.
The defender spent 16 years at the Bernabeu, winning five league titles and four Champions League trophies.
But despite being captain, Ramos had his own struggles with signing a new contract and was subsequently released this summer.
Last week, he signed a two-year contract to move to PSG having been allowed to leave Madrid by club president Florentino Perez.
Though there was some animosity over how the contract talks broke down, Ramos clearly still holds affection for his former club.
And he has now backed Mbappe to join Los Blancos at some point in his career, though hopes that move does not happen before he gets a chance to play alongside him.
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“Of course. Madrid is one of the best clubs in the world. On a historical level, the best,” Ramos told AS when asked if he would advise Mbappe to move to the Bernabeu.
“For me, great players have to go through there. But now I want him on my team. I want to win and for that I want the best to be by my side.
“Advice on a personal level I could never give. I could tell him something from experience, but I would do it in private.
“As a PSG player, I would like him to stay. I like to play with the best and Mbappe is one of them.”
The prospect of playing with Mbappe would likely have been used to persuade Ramos to reject other suitors in favour of PSG.
And it is a project that he was eager to join, hailing PSG sporting director Leonardo and manager Mauricio Pochettino’s efforts to bring him to France.
“I am adventurous and my priority was the sports project,” Ramos said.
“Also the treatment they gave me. The president, Leonardo, Pochettino… they gave me the important affection to decide.
“I like to take on these new challenges. It is always good to get out of your comfort zone. I am very happy with the decision I have made.”