Jean-Clair Todibo has completed his medical at West Ham ahead of a move to the Premier League club.
Mail Sport reported earlier this week that the Hammers had re-entered the race to sign the defender from Nice amid competition from Juventus.
The 24-year-old played a key role in Nice securing Europa League football with a fifth-placed finish in Ligue 1 last season and made 33 appearances in all competitions.
Having impressed at another of Sir Jim Ratcliffe's teams, Todibo had been strongly linked with a move to Ineos-owned Manchester United this summer before UEFA regulations on multi-club ownership put a stop to the deal.