With federal approval in hand, construction should start in December on a liquefied natural gas export facility in Freeport, Texas, the lead company said.

Freeport LNG Expansion announced it received final authorization from the Department of Energy to send gas from its planned facility on Quintana Island off the coast of Texas to countries that don't have a free-trade agreement with the United States.

The first two trains -- facilities that cool gas to liquid form -- should enter into service before the start of the next decade. Freeport LNG will have three trains.

Exporting LNG to countries without a free-trade agreement requires special consideration of the public's interest.

Supporters of LNG exports argue it would provide a source of economic stimulus, while detractors say it would lead to more hydraulic fracturing, the controversial drilling practice known also as fracking.

"This project will have a significant economic impact on this region and our nation," Freeport LNG Chairman and Chief Executive Officer Michael Smith said in a Monday statement.

The U.S. Energy Information Administration said in a report last week the increase in U.S. natural gas production from shale should support as much as 80 percent of the potential increase in demand resulting from the steady gains in LNG exports from the Lower 48 states.

EIA in an analysis found LNG exports reach 2 billion cubic feet by next year, and eventually surge to as high as 20 billion cubic feet per day.

The agency found the "effects on overall economic growth [from the emerging LNG market] were positive but modest."