Mexico's energy industry model is outdated and consumers are bearing the burden, the chairman of the conservative opposition National Action Party, or PAN, Gustavo Madero said.

"The model in Mexico is an exhausted model that is not allowing Mexicans to have cheaper energy," Madero said during an appearance Saturday in the southeastern city of Merida.

The PAN made a proposal on July 18 for reforming Mexico's energy industry that would open the way for private investors to play a role in oil production, making state-owned oil monopoly Petroleos Mexicanos, or Pemex, compete in the market.

"We have to give other actors an opportunity" where Pemex cannot or does not want to participate in oil production, Madero said.

"No other place in the world has a model like Mexico's in which only one company wants to do everything. No petroleum-producing country, no capitalist country, socialist (country), no place that has a model like Mexico's," the PAN chairman said.

Pemex has a monopoly on the production of oil and gas, as well as on the production of petroleum derivatives and the distribution of gasoline.

"This model has been exhausted, the model is called a state-owned monopoly," Madero said.

Pemex said Friday that it posted a net loss of $4.12 billion in the first half of this year.

Mexico's political leaders are expected to start looking at energy industry reforms in the next few weeks, with the focus on the future of Pemex and whether to allow private investment in the petroleum industry.

The left opposes any effort to privatize Pemex or open the oil industry to private investment.

Last week, leftist politician Cuauhtemoc Cardenas criticized the energy reform plan proposed by the PAN and expressed support for the protests planned by the left against efforts to open Mexico's oil industry to private investment.

The PAN's plan is "badly laid out, badly supported," and "has exaggerated figures on the investment requirements" of the oil industry, Cardenas told Milenio Television.

The plan is incomplete because it does not link energy reform to fiscal reforms, the key to relieving state-owned oil giant Petroleos Mexicanos, or Pemex, of its high payments to the Treasury, Cardenas, the founder of the opposition Party of the Democratic Revolution, or PRD, said.

Pemex, which posted total revenues of $131.75 billion and had assets of $161.8 billion in 2012, is the world's No. 5 oil producer and accounts for about 40 percent of the Treasury's revenues. EFE