UPDATE 1-Cheniere gives green light for US LNG export plant build

* Bechtel to begin building the $5.6 bln project

* Sabine Pass export plant completion expected in 2015

* First U.S. LNG export plant to be built since 1969

NEW YORK, Aug 9 (Reuters) - U.S. liquefied natural gas terminal developer Cheniere Energy has given the green light for construction of the first U.S. LNG export plant in a generation, which is expected to be ready by 2015, the company said in a statement on Thursday.

Bechtel Oil, Gas and Chemicals will now begin construction on the $5.6 billion project in Sabine Pass, Louisiana, that will open up vast reserves of cheap U.S. gas to needy import markets in Asia and Europe where prices for the fuel are many times higher.

The export plant, which will cool natural gas to a liquid for shipping overseas, will be built on the site of Cheniere's existing LNG import terminal which came online in 2008 but has since sat idle as record rises in U.S. domestic gas production dented import needs.

Sabine Pass LNG is expected online nearly 50 years after the Kenai export plant in Alaska - the only other U.S. LNG export terminal - was built in 1969. It will initially comprise two production units, the first arriving six to nine months before the second, the Houston-based company said. Two other units, called trains, are scheduled for 2017 and 2018.

Cheniere has already signed supply deals with buyers across the globe for nearly all the 2.2 billion cubic feet per day of capacity from the four production trains, approval for which was granted by federal regulators in April.

The customers include global LNG trader BG Group, Spain's Gas Natural Fenosa, South Korea's KOGAS and India's GAIL. BG will take supply from the first train and Gas Natural Fenosa will be supplied by the second train.

Cheniere's move to build the export plant comes as U.S. natural gas inventories sit at record highs due to prolific production from newly developed shale gas deposits.

A string of other export projects have been proposed in the United States to supply Europe and Asia.

However, for now, Cheniere looks likely to be the only project to get the go ahead. The U.S. government has suspended decisions on expanding U.S. gas exports until a study on the price impact of such exports on domestic consumers is completed late summer.