Chinese imports of liquefied natural gas (LNG) have fallen for the first time since the trade began 10 years ago.

The US Energy Information Agency has reported that LNG imports declined 1.1 per cent in 2015.

It is a further blow to Australia's fledgling and struggling coal seam gas exporters who have spent more than $75 billion building export terminals at Gladstone in Queensland alone.

It should come as no surprise that China's appetite for LNG appears to have plateaued - at least for the time being – given the rapid and well documented cooling of the economy.

The long term picture is far from rosy either with China's powerful National Development and Reform Commission downgrading its forecast for future gas demand by 14 per cent late in 2014.

The choking of demand will hit around the time when global supply is set to surge.

Excess US gas is expected to supply almost 70 million tonnes per annum (mtpa) to the global market by 2020, while Russia's Gazprom is planning to build two pipelines directly to China, supplying another 50 mpta by 2025.

Chinese LNG imports fell in 2015 for the first time on record. ( EIA )

The EIA report found Chinese LNG imports have grown steadily in the last 10 years, from 0.78 mtpa (or 0.1 billion cubic feet per day, the EIA's preferred measure) in 2006 to 10.1 mtpa in 2010, and have more than doubled since then.

Imports reached their peak in 2014 at 21.1mtpa, making China the third-largest LNG importer globally after Japan and South Korea.

However, the EIA said LNG imports declined to 20.2mtpa, reflecting in part a slowdown in the growth of the Chinese economy and lower prices of competing fuels.

China currently has 13 LNG terminals with a combined capacity of 42mtpa, with several more under construction which would boost total import capacity - excluding the Russian pipelines - to almost 70mtpa.

Many of these projects have now been delayed or mothballed due to the lack of demand.

The EIA noted the big Jieyang LNG terminal in Guangdong was completed last year, but the terminal has not been connected to a provincial pipeline network serving the industrial and domestic users.

LNG exporters are dealing with major Chinese oil and gas companies postponing contracted deliveries and instead buying lower-priced spot cargoes.

The EIA report found many contracts to supply LNG at the new regasification terminals were signed when oil prices were above $US100 per barrel, which makes long-term LNG prices less competitive than both spot LNG and LPG (Liquefied Petroleum Gas).