The Frenchman, 20, impressed last season as he bagged 19 goals and six assists in 33 appearances for the Ligue 1 outfit.
And he seemed to be set for a move to Stamford Bridge as Mauricio Pochettino eyed yet another summer signing.
But according to Foot Mercato, Wahi has “decided that he wants to join West Ham“.
It is understood he feels a switch to the Hammers is the best step for his career progression.
And if Chelsea do miss out on Wahi, they will be on the receiving end of a hijacking – having recently pinched Moises Caicedo and Romeo Lavia from under the nose of Liverpool.
David Moyes is crying out for attacking reinforcements following the departure of Gianluca Scamacca.
Michail Antonio and Danny Ings are the only recognised centre-forwards in West Ham’s squad.
And Antonio has been linked with a move to Saudi Arabia before the end of the summer window.
Wahi, who has also attracted interest from Inter Milan, has earned three caps for France’s Under-21 side, scoring one goal.
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He is so highly-rated he has been compared to former Chelsea midfielder N’Golo Kante, despite the fact they play in different positions.
The comparison with Kante, who left for a mega-money move to Al-Ittihad, comes through them both hailing from the small Paris suburb of Courcouronnes.
And each started their football careers at the local amateur club JS Suresnes and, like the star midfielder, Wahi spent every spare second at their Maurice-Hubert stadium honing his skills.
Those similarities saw Le Parisien dubbing the young Frenchman “Kante’s little brother”.
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