Buyout group Apollo Global Management and Brightstar founder Marcelo Claure are in discussions with Millicom International Cellular over a potential takeover.
Such a takeover could value the Latin America telecoms company at $10 billion, including debt, the Financial Times reports.
Millicom confirmed discussions over a potential acquisition, specifically noting Apollo and Claure Group directly.
In the brief statement, Millicom added: "There is no certainty that a transaction will materialize nor as to the terms, timing or form of any potential transaction."
The FT notes that Apollo and Claure are looking to structure a bid in a way that would avoid them repaying or refinancing about $6.9bn of Millicom’s existing debts.
Apollo has form for big acquisitions, with the company behind the $7.5bn acquisition of Lumen's Brightspeed business unit in October of last year.
Meanwhile, Claure founded mobile phone distributor Brightstar in the 1990s before selling the business to Japanese giant Softbank for $1.5 billion in 2014. He was also president and CEO at US operator Sprint, prior to its merger with T-Mobile.
Although Millicom is based in Luxembourg, the company mainly operates in Latin America under its Tigo brand, and provides mobile and cable services.
Shares in Millicom jumped by as much as 23 percent following reports of the negotiations.