Monaco have made an offer for Tiemoue Bakayoko.
The Ligue 1 club are looking to re-sign their former player on loan for the rest of the season with a view to a permanent move.
Bakayoko, 24, has failed to impress at Chelsea since arriving from Monaco two years ago.
Turkish club Galatasaray have also enquired about the midfielder, who spent last season on loan at AC Milan.
He made 29 Premier League appearances for Chelsea during the previous season, scoring twice.