MEXICO CITY, Dec 16 (Reuters) - Mexico's telecommunications regulator IFT has approved a plan from dominant broadcaster Televisa that lays out how the company will share infrastructure with competitors in order to avoid stiff penalties tied to its share of controlling more than half the market, the watchdog said on Tuesday.

The plan is part of a process that Televisa, the world's biggest provider of Spanish-language television content, must complete in order to trim its market share since being named the sector's dominant player by the regulator earlier this year.

The Televisa plan approved by IFT covers so-called passive infrastructure, including masts, towers and other transmission equipment.

A sweeping telecommunications reform signed into law by President Enrique Pena Nieto last year seeks to curtail the market power exercised by Televisa as well as tycoon Carlos Slim's America Movil in the mobile and fixed line telephone sector.

(Reporting by David Alire Garcia; Editing by Ken Wills)