The explosive growth in LNG consumption seen in recent years has stalled on cooling Asian economies and with a resumption of nuclear energy and a greater use of coal in some markets.
At the same time, new LNG production has been coming on stream, meaning tight supply conditions that had been expected to last until the end of the decade are ending more quickly.
"Demand is a lot weaker than we anticipated just six months ago," said Gavin Thompson, head of Asia-Pacific gas and power at consultancy Wood Mackenzie.
Asian spot LNG prices have more than halved since the start of the year to below $10 per million British thermal units (mmBtu).
Average import prices into Japan, the world's top buyer, are forecast to fall to about $11 per mmBtu next year, down from an estimated $15.50 this year and $16.45 in 2013, if Brent crude averages around $75 a barrel, according to David Hewitt, co-head of global oil and gas equity research at Credit Suisse.
If Brent trades at $85 next year, the price could be $12.60 per mmBtu, Hewitt said.
Japanese prices are a benchmark for LNG in Asia, a region which accounts for about 70 percent of global trade.
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