America Movil’s mobile and fixed line operations are likely to face further scrutiny, with the announcement of a further probe by the Federal Telecommunications Institute (IFT), Mexico’s telecoms regulator.

Both Telcel and Telmex could be impacted by the IFT inquiry, announced in the government’s official gazette.

The announcement said the regulator will determine which operators hold substantial market power in voice, data or video services and networks, both nationally and at state, regional or local levels.

The inquiry, which could also pull in Televisa, the country’s largest TV player, will not exceed 90 days. It will look at market practices, and whether leading operators are using their power for unfair advantage.

America Movil has been under growing pressure in Mexico since IFT declared the operator a “preponderant economic agent” and hence eligible for tougher rules to curb its dominance. That definition was an assessment based on market share.

The company subsequently responded by putting parts of its business up for sale, in an attempt to reduce its reach.

Numerous reports have said America Movil will dispose of operator assets on Mexico’s east coast, as well as the west coast and near the US border. And foreign players have been linked to the assets — including AT&T, SoftBank and Bell Mobility. But so far no sale has taken place.

AT&T subsequently inked a deal to acquire Iusacell.