“We are not buyers,” Xavier Niel said during an interview with BFM radio on Tuesday.
“The market’s consolidation cannot happen without us so there will be no consolidation.”
Previously a fixed-line operator, the arrival of Niel’s offering in the French mobile arena in January 2012 sparked a price war that has fueled open talk of consolidation this year.
Third-place player Bouygues has been seen as a takeover target after it lost a battle to buy bigger rival SFR to cable group Numericable NUME.PA.
Market leader Orange (ORAN.PA) called off talks towards a possible bid for Bouygues in early July, while speculation that Iliad may make a move waned when Niel made a bid for T-Mobile US TMUS.N in August.
But Iliad, in which Niel holds 55 percent, dropped its bid last month, reviving hopes it might instead focus on growth and acquisitions in France.
Shares in Iliad were 0.76 percent lower in early morning trading, while Bouygues shares were 0.4 percent higher.
Reporting by Pascale Denis and Natalie Huet; Editing by Blaise Robinson and Andrew Callus