The Frenchman, 22, has become a mainstay for the Ligue 1 side, having made 50 appearances in the last stint.
He has previously been linked with the likes of Paris Saint-Germain, Liverpool, Manchester United and Chelsea.
However, according to athleticReal Madrid and Monaco have agreed a deal and are finalizing paperwork before announcing his transfer to the Spanish capital.
The report says that Tchoumeni has recently decided to move to the Bernabeu.
His decision will be a blow to Manchester United and Chelsea who are looking for a central midfielder to bolster their squad ahead of next season.
Tchouameni’s rise has seen him become a regular starter in the French national team, making 10 appearances over the past two years.
Meanwhile, he was also included in the Ligue 1 Team of the Year in the last two seasons.
United and Chelsea are both reportedly interested in Declan Rice, but with West Ham seeking more than £100million, Tchoumeni seemed a viable option.
United will turn their attention to Frankie de Jong but recent reports suggest the Dutchman would prefer to stay at Barcelona.
Speaking last month, the manager of the Spanish side indicated that de Jong could be sold due to the club’s lack of cash.
Xavi said: ‘He is a fundamental player, but then there is the financial condition of the club.’
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