The Hammers have brought in Nayef Aguerd from Rennes but he is currently on the treatment table having picked up an injury in pre-season that required surgery.
They also recently accepted a bid of around £17m from fellow London club Fulham for French defender Issa Diop, which will leave them short of options at centre-half.
To reinforce their backline, West Ham are considering entering the race for at least one of Les Parisiens’ defenders in Diallo and Kehrer, according to French outlet Foot Mercato.
Both are yet to feature under new boss Christophe Galtier thus far this season, with Sergio Ramos, Marquinhos and Presnel Kimpembe comprising the preferred first-choice defensive unit, while they have also added Nordi Mukiele from Leipzig to their options.
During the 2021/22 season, Diallo made 16 appearances in all competitions, assisting once and earning two cautions but playing primarily at left-back.
In the same time, Kehrer made 34 appearances in all competitions, scoring a pair of goals and earning three cautions, with a majority of his game time coming at right-back.
Kehrer has entered the final year of his current contract and is on Sevilla’s radar, with his wages potentially posing a problem for West Ham, while Diallo, briefly considered by the Hammers in January amid injury troubles for Kurt Zouma and Angelo Ogbonna, is wanted by both Napoli and AC Milan.
Their versatility is highly valued by the Hammers and it could happen that one, maybe even both, could swap the Parc des Princes for the London Stadium before the transfer window closes.