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Jan 9 (Reuters) - U.S.-based Commonwealth LNG has received a 20-year authorization from the Department of Energy to export liquefied natural gas from its proposed Louisiana facility to countries without free trade agreements with the United States.

The company has also received an approval for a period of 25 years for exports to FTA nations.

The authorizations will become effective either when the facility starts exporting commercially or seven years from the date the permission was granted.

Commonwealth has been attempting to build the country's first integrated LNG export facility, where its major shareholder Kimmeridge will supply gas from its Eagle Ford shale production to the plant.

It has also signed supply agreements with EQT EQT.N, Glencore GLEN.L, Japan's biggest power generator JERA, Malaysia's Petronas PGAS.KL and Australia's Woodside Energy WDS.AX.

Commonwealth has so far sold 5 million metric tons per annum of planned capacity, but is still short of selling out the total 9.5 mtpa that would come online upon completion.

LNG developers typically reach a final investment decision on projects once they have secured enough supply deals to obtain the necessary financing for construction.

The company had secured final non-FTA export authorization from the energy department for its export facility in September last year.

Its Louisiana facility is designed to produce 9.5 million tonnes of LNG annually and had received approval from the Federal Energy Regulatory Commission in 2025.

(Reporting by Pooja Menon in Bengaluru; Editing by Shilpi Majumdar)

((Pooja.Menon@thomsonreuters.com;))