Marseille are looking to cash in on the striker before the transfer window slams shut and have put an asking price on his head of €15m.
Nice are also keen, but only want Dieng on loan while, according to French outlet Foot Mercato, Lorient have now made the striker a priority.
They also want Dieng on loan, but in bad news for the two French sides, the striker is claimed to be waiting for an offer from England.
Marseille also want bids to come in from England as they look to offload a player not in the plans of coach Igor Tudor.
Dieng scored seven times in Ligue 1 last season as Marseille finished the campaign as runners-up.
The 22-year-old also featured heavily for Marseille in their runs in both the Europa League and Europa Conference League, with the club reaching the semi-final of the Europa Conference League; he scored in the first leg, against Feyenoord.