Houston-based Cheniere, which has regulatory approval to build the United States' first LNG export plant in a generation, has been seeking funds to start construction.

News of CIC's deal comes at a time of increased focus on China's investment in the energy sector in North America. Last month, China's state-owned CNOOC Ltd (0883.HK) launched an agreed $15.1 billion takeover of Canadian oil producer Nexen Inc (NXY.TO), in what is set to be China's biggest ever overseas acquisition.

Asian state-owned companies have stepped up purchases of overseas energy assets as they scramble to secure energy resources required to support their economic growth.

In June, Malaysian state oil company Petronas launched a C$4.8 billion takeover of its Canadian joint-venture partner Progress Energy Resources Corp (PRQ.TO).

Cheniere Energy has also seen strong interest from Asia-based institutions. In May, Singapore state investor Temasek Holdings TEM.UL and Asia-based private equity firm RRJ Capital agreed to invest $468 million in the company.

Private equity firm Blackstone Group LP (BX.N) was one of the early backers of Cheniere, when it agreed to invest $2 billion into the company in February.

The Financial Times, which first reported the investment but gave no deal value, said Blackstone advised CIC on the deal. CIC will have no direct influence on Cheniere, the report added. China's $482 billion fund is likely to escape scrutiny with its latest purchase as it is co-investing along with other institutions, the report added.

A CIC spokeswoman declined to comment, while Blackstone and GIC were not immediately available for comment. The source declined to be identified as the details of the deal were not public.

(Additional reporting by Gui Qing Koh and Saeed Azhar; Writing by Denny Thomas; Editing by Richard Pullin and Muralikumar Anantharaman)

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