Japan's Softbank and KDDI are protesting a decision by NTT Com to sell wholesale access to its fiber broadband services to mobile operators, citing concerns of a return to monopoly.
NTT Com has announced a plan to offer fiber services to mobile operators to let them resell the services as part of their contracts, Reutersreported.
Subsidiary NTT DoCoMo now plans to bundle mobile and NTT Com broadband services into single packages.
But Softbank and KDDI have both publicly expressed concerns that the decision could allow NTT to restore its monopoly position, and thus give it carte blanche to control broadband prices.
At present, NTT DoCoMo is the only one of Japan's three mobile operators not to offer bundled fiber services. KDDI has its own network, while Softbank offers plans in collaboration with NTT Com.
NTT has insisted it will be fair with its pricing, asserting that it will rent its fiber network based on traditional competitive rules.
Complicating matters, NTT Com is still 36% owned by the Japanese government.