Nancy have set Celtic a deadline to meet their asking price for Landry N'Guemo.
The Scottish Sun says the French side have given the Hoops until Thursday to take up their £1.8million buy-out clause for the Cameroon midfielder.
Sunderland, Wigan and Birmingham are all eyeing N'Guemo and Nancy sporting director Nicolas Holveck said: "Celtic have the priority until June 10 - but if it's not taken up by then we will study the other offers we have from the English Premier League."