MEXICO CITY -- Leaders of Mexico’s three major political parties launched a sweeping proposal Monday to break open the highly monopolistic telecommunications sector, calling for new laws that would create competition to the established companies that now control the nation’s broadcast and cable television, Internet access, and fixed line and cellular telephones.

The proposal would open the door to two new national television networks and set rules that would lower costs and broaden access to the Internet and telephones. It also would allow dramatically increased foreign investment in telecommunications.

In a ceremony filled with pomp, chiefs of political parties from the left, center and right cast the telecom reform as a watershed event that would shake off monopolistic private control that is almost without parallel elsewhere in the Western world.

President Enrique Pena Nieto, who just completed 100 days in office, said opening up the telecom sector to competition would invigorate the economy and lift Mexico globally.

“In the era of knowledge and information, it is a new form of illiteracy not to have access to them,” he said of modern digital platforms.

Neither Pena Nieto nor any of the political party leaders portrayed the proposed constitutional reform as targeted at the wealthy tycoons who keep a monopolistic grip on telecommunications. Yet the proposals are likely to vastly affect the interests of several of Mexico’s most powerful figures.

They include Carlos Slim, the world’s wealthiest man with a $71.5 billion fortune, whose wireless company, America Movil, controls roughly 70 percent of the cellular market in Mexico and whose fixed line company, Telefonos de Mexico, better known as TelMex, controls 80 percent of all fixed-line phones in the country.

High rates keep Mexicans from using cellular phones as much as residents of other Latin American countries.

Beside him in the billionaire’s pantheon is Emilio Azcarraga, controlling shareholder in Televisa, the world’s largest Spanish-language broadcaster and magazine publisher. Grupo Televisa controls 70 percent of the Mexican television market.

Following the ceremony, a tweet from Azcarraga’s Twitter account acknowledged the threshold of a new era: “Time of great challenges and also of opportunities. Competition welcome,” the tweet said.

Slim did not offer an immediate comment on the reform.

A third tycoon, Ricardo Salinas Pliego, and his Grupo Salinas, are controlling shareholders of TV Azteca, which commands most of the remaining 30 percent of the television market in Mexico not controlled by Televisa.

Before the constitutional amendments involved in the telecom reform become law, they must pass through both chambers of Mexico’s Congress and be approved by a majority of state legislatures.

If successful, it would mark the second major reform of Pena Nieto’s nascent administration. Within days of taking office Dec. 1, Pena Nieto’s Institutional Revolutionary Party, or PRI, formed an unprecedented political alliance with two other major parties, called Pact for Mexico, and announced broad objectives for reforming the state.

The parties quickly enacted an education reform that took away from a 1.5 million-member teachers union the power to hire and fire teachers. Further signaling an intent to shake up the field, prosecutors arrested powerful teachers union leader Elba Esther Gordillo on Feb. 26 and charged her with siphoning off hundreds of millions of dollars in union funds.