NEW YORK (AP) - French telecom company Iliad SA has made a bid for T-Mobile US Inc., the country's fourth-largest cellphone company, according to a published report.

NEW YORK (AP) French telecom company Iliad SA has made a bid for T-Mobile US Inc., the country's fourth-largest cellphone company, according to a published report.

The Wall Street Journal said Thursday that Iliad is trying to snap up T-Mobile before it's sold to Sprint Corp., the No. 3 U.S. cellphone carrier. That deal has been rumored for a long time, but has not been announced. Analysts believe U.S. regulators are likely to block the T-Mobile/Sprint pairing due to concerns that it would reduce competition.

Iliad is much smaller than T-Mobile US, and the Journal said it was bidding only $16 billion. T-Mobile US's market capitalization was $25 billion before the stock shot up 4.3 percent in midday trading, after the paper's report.

Iliad and T-Mobile US had no immediate comment.

Iliad and T-Mobile US are both industry mavericks. Under CEO John Legere, T-Mobile US has thrown out the standard two-year service contract and introduced new plans that allow for more frequent phone upgrades, a move quickly copied by the larger carriers. Iliad broke onto the French scene with the Freebox, a unit that combines Internet access, TV and phone service over broadband lines. In 2012, it started offering cellphone service as well.

Iliad has 5.7 million broadband subscribers and 8.6 million wireless subscribers. T-Mobile US has 50.5 million subscribers on its wireless network.

T-Mobile US is controlled by Deutsche Telekom AG of Germany, which owns 67 percent of the stock. A similar portion of Sprint's stock is owned by Softbank Corp. of Japan.