Oct 25 (Reuters) - U.S. liquefied natural gas (LNG) company Cheniere Energy Inc (LNG.A) said on Monday that its marketing arm will sell LNG to a unit of Glencore PLC (GLEN.L), moving Cheniere"s proposed Stage 3 expansion of its Texas export plant closer to approval. The deal is one of several announced in recent weeks as LNG buyers seek to lock in long-term supplies and prices of the super-cooled fuel as global energy shortages boost prices to record highs.Utilities around the world are competing for LNG cargoes to fill dangerously low gas stockpiles in Europe ahead of the winter heating season and meet insatiable demand for the fuel in Asia where coal and gas shortages have already caused power blackouts in China. Under the sale and purchase agreement (SPA), Cheniere said Glencore, an Anglo-Swiss commodity trading and mining firm, agreed to purchase approximately 0.8 million tonnes per annum (MTPA) of LNG from Cheniere Marketing on a free-on-board basis for about 13 years beginning in April 2023. The purchase price of the LNG will be indexed to prices at the U.S. Henry Hub gas benchmark in Louisiana, plus a fixed liquefaction fee, Cheniere said. "This SPA further builds upon Cheniere"s commercial momentum, marking another important milestone in contracting our LNG capacity ahead of an FID (final investment decision) of Corpus Christi Stage 3, which we expect to occur next year," Cheniere CEO Jack Fusco said in a release. Cheniere"s Corpus Christi Stage 3 would add up to seven mid-scale liquefaction trains that would produce around 10 MTPA of LNG. Earlier this month, Chinese gas distribution company ENN Natural Gas Co Ltd (600803.SS) agreed to buy about 0.9 MTPA of LNG from Cheniere in a 13-year deal. read more Separately, units of China Petroleum and Chemical Corp (600028.SS), or Sinopec, agreed to buy LNG from Venture Global LNG, another U.S. LNG company. read more