It marks the completion of sales agreements from Sabine Pass and opens the way for the first US LNG export plant in nearly fifty years. Soon consumers across the globe could be burning natural gas from the United States, where supply continues to outstrip demand.

State-run Kogas, South Korea’s sole gas wholesaler, will buy 3.5 million tons per year (mtpa) of LNG from the third of four production units planned for Sabine Pass, known as Train 3, which is expected to be online in 2017. Train 1 is scheduled for 2015, pending federal regulatory approvals.

“KOGAS is our fourth foundation customer and we have now sold 16 mtpa of the 18 mtpa being developed at the Sabine Pass LNG terminal,” said Cheniere chief executive Charif Souki in a statement.

Cheniere plans to keep the remaining 2 mtpa — 0.5 mtpa from each 4.5-mtpa train — for its own portfolio.

Record natural gas production due to the prolific development of shale deposits across the US has left the country with decades of supply, but has pushed prices way below global levels.

LNG, which is natural gas cooled to a liquid for shipping, is more than five times dearer in Asia, prompting a string of US export plant proposals over the past year. Concerns have been raised by consumer groups that US gas prices will be pushed higher by exports.

The total capacity of Sabine Pass amounts to about 2 billion cubic feet per day of gas, or three percent of daily US production.

Kogas will buy LNG from Cheniere for $3 per million British thermal units, plus a 15 percent premium to US benchmark gas prices at Henry Hub. The amount is higher than the first agreement that Cheniere signed with Britain’s BG Group in October which agreed a fixed fee of $2.25 plus the 15 percent premium to US prices.

Previous deals were signed since October with BG Group, Spain’s Gas Natural Fenosa and GAIL India.