At an investor conference in Boston on Wednesday, T-Mobile's Chief Financial Officer Braxton Carter said that French firm Iliad SA's $15 billion bid for acquiring T-Mobile is a "very inadequate" proposal.

The statement by Carter comes in the wake of the fact that third-ranking US wireless carrier Sprint has recently announced that it is withdrawing its proposed bid for the acquisition of smaller rival T-Mobile. With Sprint having ended the talks of T-Mobile acquisition, Iliad is now left as the sole bidder for T-Mobile.

About Iliad's $15 billion offer to acquire a majority stake - to the tune of 56.6 percent - in T-Mobile, Carter said that the bid by the French firm is too low, particularly when the growth prospects of T-Mobile are concerned.

Iliad had put forth its '$15 billion in cash' offer for acquiring majority stake in T-Mobile last month. According to a Bloomberg News report, the French firm is apparently seeking financial assistance from partners to go ahead with the bid, and even probably enable it to make an offer for a larger stake.

With regard to Iliad's offer for T-Mobile, Carter said at the conference that "Very rarely do people come with their best bid to start;" and added: "We believe today that we're undervalued. And we believe that our forward potential is significant."