Manchester United have reportedly been informed that they will have to come up with an offer of €3m (£2.7m) in order to sign Sochaux defender Willy Kambwala this summer.
The Frenchman's performances at youth level are believed to have caught the attention of United, who are said to have recently submitted an offer of less than €1m (£900,000).
However, according to L'Equipe, Sochaux have told Ole Gunnar Solskjaer's side that a bid of €3m (£2.7m) will be required before they can open contract talks with the 15-year-old.
The report claims that the 20-time English champions are yet to signal whether they would be prepared to meet Sochaux's asking price for the France Under-16 international.
The 20-time English champions will face Sevilla in the Europa League semi-finals on Sunday night.