A French telecommunications company has presented a bid for T-Mobile, offering $15 billion in cash at $33 per share.

Though smaller than the company it proposes to buy, Iliad's bid could further complicate Sprint and SoftBank's hopes to wrap up a deal to acquire T-Mobile.

Sprint, backed by SoftBank, has a tentative deal in place to purchase T-Mobile for $32 billion at $40 per share. While Iliad's offer comes in below Sprint's bid, the French wireless carrier stated that it and T-Mobile were kindred souls and indicated that the companies could produce billions in synergies.

"The U.S. mobile market is large and attractive," Iliad stated. "T-Mobile US has successfully established a disruptive position which, in many ways, is similar to the one Iliad has built in France."

Back in France, Iliad has been at the center of a warring mobile industry that has been trying to consolidate to stay afloat. While Iliad's bid for T-Mobile was a long shot, shares of each of France's wireless carriers fell in reaction to the offer. Iliad's shares fell due to investor doubt that the wireless carrier could manage the acquisition, while other carriers were hurt by pessimism surrounding the future of the consolidation effort.

Frank Heise, fund manager at Metzler Asset Management and Iliad investor, said he wasn't sure if Iliad's offer was a serious bid to buy T-Mobile. Iliad wanted to pressure its rivals in France to show them that it doesn't need them, said Heise.

"Iliad has shown in France that it can roil a market with its low cost base," said Heise. "But that may not work so fast and easily in the U.S., where the market conventions are different: higher average revenue per customer, different product packages, more promotion expenses."

There have been reports stating T-Mobile's parent company, Deutsche Telekom AG, has rebuffed Iliad's offer. But with the backing of BNP Paribas and HSBC, the French company could present T-Mobile with another offer if it really was serious about the acquisition. 

Whether or not Iliad's bid for T-Mobile was serious, it has further strained Sprint's deal to acquire the United State's fourth-largest wireless carrier. U.S. regulators have already rejected a bid from AT&T to purchase T-Mobile in 2011 and have indicated that they were against Sprint as well.

Iliad would likely escape much of the hesitancy U.S. regulators have expressed with regard to Sprint's bid, because the French company's purchase of T-Mobile would allow the U.S. wireless market to maintain its count of four major carriers. Jan Dawson, an analyst with Jackdaw Research, said Iliad's offer, at the very least, forces Sprint's hand.

"This probably throws a wrench in SoftBank's plans," said Dawson. "With another potential bidder, they may not be able to wait this out. It probably forces them to act faster and could raise the price they were willing to pay."