France's Economy Ministry has brought a court case against Amazon with a view to fining the internet giant €10 million.
The ministry claims the US company imposed overly restrictive commercial clauses on companies selling on its French platform.
A spokeswoman for the ministry confirmed the information to the Luxembourg Times on Monday.
Speaking to news agency AFP, Loïc Tanguy, director of DGCCRF (Direction générale de la concurrence, de la consommation et de la répression des fraudes), said the organisation led an investigation into all markets.
"We considered that, in clauses imposed by Amazon on companies selling on the marketplace, there was a significant imbalance, a practice that is prohibited by the code of trade.
"We have asked for a fine of around €10 million."
He said other platforms such as Cdiscount and Rue du Commerce also had clauses the DGCCRF objected to but added that those companies made changes to comply as soon as a request for modification was made.
"We therefore didn't take it any further," Tanguy said in his interview with AFP.
French newspaper Le Parisien reported that Amazon could modify or suspend contracts at any point, including imposing shorter delivery times overnight.
When delivery problems, occur the responsibility falls on small vendors and not on Amazon, the report claims.
On Friday, the Luxembourg government announced it would appeal the European Commission's order to collect €250 million in back taxes from Amazon.
The Commission ruled in October that Luxembourg had granted undue tax benefits to Amazon that amounted to illegal state aid.
The Luxembourg government said it believed the Commission failed to establish the existence of a "selective advantage".
"This appeal seeks to obtain legal certainty and does not put into question Luxembourg's strong commitment to tax transparency and the fight against harmful tax practices," the statement said.