MEXICO CITY (Reuters) - Mexican telecoms giant America Movil <AMXL.MX>, controlled by tycoon Carlos Slim, said on Monday its Mexican unit had reached an agreement to provide a national roaming service to its main competitor in the local market, Telefonica Mexico.

America Movil serves two-thirds of the Latin American country's mobile phone market, followed by Spain's Telefonica, which operates in Mexico under the Movistar brand.

(Reporting by Natalie Schachar and Noe Torres; Editing by Subhranshu Sahu)