The 27-year-old has been in fantastic form this season, averaging 3.6 tackles, 3.1 interceptions, 1.1 successful dribbles and 1 created chance per match from 32 Ligue 1 appearances.
The former France U21 began his career as a wideman but has produced the aforementioned form as a full-back this term, featuring on both flanks of the Nice backline but predominately at right-back.
Therefore, the 5 foot 8 star could solve a real problem for the Hammers; winger Michail Antonio has been utilised as an emergency No.2 in recent months following an injury to loanee Carl Jenkinson, who will return to parent club Arsenal this summer.
And with his Allianz Riviera contract due to expire at the end of the campaign, the Hammers are in line to snap up the former Lyon star on a free transfer.
However, the east London outfit face competition from Saint-Etienne.