This has been a turbulent week in Mexico, where leftist militants continue to hold both houses of Congress in protest of an energy reform bill sent to the legislative body by President Felipe Calderon. As VOA's Greg Flakus reports from Houston, both sides in the conflict say they are fighting for the country's energy future.

On Thursday militants from the leftist Party of the Democratic Revolution, or PRD, along with representatives of other leftist parties took to the streets outside the Mexican Congress building while elected members from those parties went inside and staged a takeover.

The disruption of normal legislative routine was not unprecedented. The same groups had tried to block the inauguration oath of President Felipe Calderon when he took office in December, 2006. Such disruption is beyond the authority of the police and security guards who protect the Congress because the action is being carried out by elected members of the legislative body.

Former PRD presidential candidate Andres Manuel Lopez Obrador, who is widely seen as the intellectual author of the takeover, spoke to the Mexican people in a radio address to explain his position.

He says it is vital to stop the energy reform bill sent to Congress by President Calderon because it is merely a veiled attempt to privatize the state-owned energy sector. He says the future of Mexico depends on keeping the nation's oil and gas reserves out of the hands of private investors, especially foreign investors.

President Calderon, in presenting his reform package Tuesday, argued that the future of Mexico depends on just such an opening to private companies.

He says Mexico's state-owned oil company, PEMEX, does not have the resources or technology to exploit known reserves in the Gulf of Mexico and that production from current wells is declining. Mexico, which is currently ranked as the world's fifth largest oil producer, nationalized its energy industry in 1938.

Experts say in ten years time Mexico will not be producing enough oil to meet its own needs, let alone have oil to export, unless new production can be brought online soon. The energy reform bill would allow a limited opening to private companies to share in oil revenues with PEMEX in exchange for developing new fields. The proposal would also allow foreign participation in building refineries. Mexico currently relies on imports of some gasoline from the United States because of its lack of refinery capacity.

Calderon also argues that his proposal would create hundreds of new jobs and sources of revenue for the country that would help reduce poverty. With backing from his own National Action Party and members of the Institutional Revolutionary Party that once ruled Mexico for seven decades, Calderon saw an opportunity to get the measure passed in the legislature, but the minority leftist parties, led by Lopez Obrador are planning major disruptions all over the country to block any progress on the bill.

A top Mexico expert in the United States, George Grayson of the College of William and Mary, who is also author of a book about Lopez Obrador, says the firebrand leftist leader is unlikely to engage in dialogue to resolve the dispute.

"Lopez Obrador lives in his own world," says Grayson. "He is completely out of touch with the global economy and he claims that, somehow, by taxing the rich money can be developed so that PEMEX can do the drilling and build the refineries and construct the pipelines that will be necessary to keep Mexico from transforming from an exporter nation to an importer nation."

Lopez Obrador and his defenders argue that no plan involving the nation's oil and gas resources should be considered partly because of the scandalous outcome of privatizations in the early 1990's, which most Mexicans view as having been disadvantageous to the country.

But leading political commentators and intellectuals like historian Enrique Krauze have called on Lopez Obrador and his followers to end their takeover of the Congress. They say that is the forum where democratically elected officials should discuss and debate the reform proposal in all its aspects. Ruling party officials say they will not bow to pressure and threats of violence in order to end the standoff.