July 31 (Reuters) - French telecoms operator Iliad has made a buyout offer for T-Mobile USA Inc, the Wall Street Journal cited sources as saying, a surprise bid that counters an offer by Sprint Corp.
Details of the offer, which was made to T-Mobile's board, were unclear but the Journal cited one of its sources as saying it involved control of the company.
Shares in T-Mobile were up 4.5 percent at midday. Iliad and T-Mobile were not immediately available for comment. (Reporting by San Francisco newsroom)