(Corrects headline to America Movil)
MEXICO CITY, Jan 24 (Reuters) - Mexico's telecommunications regulator, which is investigating the market power of billionaire Carlos Slim's America Movil, could boost competition by declaring the mobile phone company dominant, a rival operator said on Friday.
Iusacell, the country's third-largest mobile operator by number of customers, would benefit if the Federal Telecommunications Institute (IFT) declares America Movil and its fixed-line subsidiary Telmex dominant.
That would enable the regulator to apply so-called asymmetric rules to level the playing field for smaller operators, as part of a wider telecommunications reform approved last year by Mexico's government.
America Movil has about 70 percent of the mobile market, while Telmex controls about 80 percent of the country's fixed lines.
"If the IFT determines America Movil and Telmex dominant, it would be very positive for competition in the industry," Eduardo Ruiz, telecommunications regulatory compliance director of Grupo Salinas, said in an email.
Iusacell is a joint venture between broadcaster Grupo Televisa and billionaire Ricardo Salinas' privately owned Grupo Salinas.
Iusacell, however, said it was concerned that IFT has not consulted it over the investigation.
The regulator has not asked the company for information, "and that concerns us regarding the market dominance declaration," said Grupo Salinas' Ruiz.
"You can only get a full picture of competition in the industry if you ask all players for information."
Asymmetric regulation would "guarantee interconnection with the dominant player at non-discriminatory terms, conditions and rates," according to a Iusacell letter addressed to the regulator and seen by Reuters.
Televisa and America Movil have said they received official notice at the end of last year that IFT was investigating whether they were dominant in their markets.
America Movil and Televisa declined to comment on Friday. Telecom regulator IFT also declined to comment.
(Reporting by Simon Gardner, Dave Graham, Elinor Comlay and Tomas Sarmiento; Editing by Jonathan Oatis)