It is not clear how much Iliad would pay for the company, or the terms of the offer. Iliad is reportedly working with several banks to secure financing for the offer.
Iliad's offer counters Sprint's (S) earlier offer for T-Mobile. Shares of Sprint are falling following the announcement.
News of the bid comes after T-Mobile's second quarter results, in which the carrier announced that it added 1.5 million in the quarter.
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