The head of the French Banking Federation has formally warned France's finance minister that he country's banks may be forced to close as many as 40,000 bank accounts by the end of the year, owing to problems these banks have in complying with the U.S. tax information reporting law known as FATCA.The 40,000 bank accounts in question are understood to be those of individuals who are either Americans or dual American and French citizens. The fact of their American citizenship obliges banks in France and elsewhere around the world to provide data on these clients to a French agency that subsequently supplies it to the U.S., as the Foreign Account Tax Compliance Act requires.In his letter to French foreign minister Bruno Le Maire, dated July 17, French Banking Federation chairman Laurent Mignon noted that France's banks say they face significant financial penalties from the U.S. if they fail to provide it with such information as the so-called Tax Information Numbers (TINs) of all of its American clients, and yet, he explained, they are unable to do this because many of these "French-speaking [French] citizens born on American soil" lack "lack any concrete link with the United States, where they no longer reside," and therefore don't have TINs or other documentation the U.S. is seeking