** Shares in Mexican telecommunications operator America Movil AMXB.MX slipped more than 2% after missing fourth-quarter earnings estimates

** J.P. Morgan analysts describe "lackluster performance" in America Movil's largest operations, including in Mexico and Colombia

** Revenues in Mexico slowed, with executives cautioning they were monitoring pre-paid clients in the country on concerns of a slowdown in the local economy

** Analysts express concern of a recent constitutional reform in Mexico on oversight of the sector, with America Movil executives saying they are monitoring for impacts

** A possible divestment of AT&T T.N Mexico "to the government would only increase fears of a government overtake of wireless segment," Scotiabank analysts write

** America Movil maintains 2024-2026 spending plan around $22 billion, plus the Chile integration of its JV with Liberty Latin America LILA.O

** Mexico City-traded shares are down to 14.87 pesos a share, while New York ADRs are also down around 2%

(Reporting by Kylie Madry)

((Kylie.Madry@thomsonreuters.com))