UPDATE 3-Mexico telecoms bill would put pressure on Slim, Televisa

* Reform aims to reduce America Movil's, Televisa's dominance

* America Movil shares down 2.65 pct; Televisa shares down 1.58 pct

* Proposal also introduces new telecom regulator

MEXICO CITY, March 11 (Reuters) - Mexico's government on Monday presented a reform bill that aims to loosen billionaire Carlos Slim's hold on the telecommunications market and curb top broadcaster Televisa's rule of the airwaves, according to a draft copy of the document.

The bill will allow greater investment by foreign companies in Mexico's television and phone markets, which could increase pressure on Slim's America Movil and Emilio Azcarraga's Televisa.

The proposed reform is expected to benefit Latin America's second biggest economy by lowering the prices consumers pay for telephone, internet and television services through greater competition, the government says.

Mexico's peso strengthened to its highest point in 18 months early on Monday with traders saying the currency had benefited from optimism on the country's reform drive.

The country's benchmark IPC stock index slipped 0.65 percent, dragged down by Slim's America Movil and Televisa, which fell 2.94 percent and 1 percent respectively.

Televisa and a spokesman for Slim declined to comment on the reform before it was presented, saying they did not have details of the plan.

Details of the reform, announced at a press conference in Mexico City, were not immediately available.

Slim controls about 70 percent of Mexico's mobile market and about 80 percent of fixed lines through his America Movil phone company. Televisa, controlled by media tycoon Emilio Azcarraga, has about 60 percent of the broadcast market.

Economists say the tycoons' control of their respective markets has subjected Mexicans to relatively high prices for services and dragged on the country's productivity as a whole.