Colombian lawmakers shelved a bill designed to challenge the dominance of America Movil in the mobile-phone industry, a victory for a company besieged by regulatory crackdowns in Latin America.

A Senate committee voted 6-3 to drop the measure, which would have restricted any carrier from controlling more than 30 percent of the market, according to a statement yesterday on the government’s website. Senators argued that Colombia’s constitution already includes measures to address anticompetitive behavior.

The decision allows America Movil, whose Claro unit has 62 percent of Colombia’s mobile-phone lines, to hold on to subscribers it would have had to shed under the proposed law. The company, controlled by billionaire Carlos Slim, is contending with government-mandated fee cuts in Brazil and a new Mexican law that may force it to share infrastructure.

“Claro’s power is very great, and the government also didn’t promote or defend the bill,” said Jorge Enrique Robledo, one of the proposal’s sponsors. “We’ll keep fighting.”

An America Movil press official declined to comment.

Colombia is planning an auction this year for licenses to use public airwaves for 4G, or fourth-generation, wireless services. The offer includes rules that would limit America Movil to frequencies that are more expensive to operate.

Lawmakers are also working on a measure that would do away with contracts that require wireless customers to stay with a provider for a set time frame, Robledo said in an interview.

Colombia and Panama make up America Movil’s third-biggest division after Mexico and Brazil, representing 9.5 percent of sales.

America Movil was unchanged at 12.54 pesos at the close in Mexico City, where it is based. The shares have dropped 16 percent this year.