Centrica has signed a 20-year agreement with Cheniere Energy Partners, to buy 89 billion cubic feet (BCF) of annual liquefied natural gas.
Under the deal, the first commercial delivery is expected to be take place in September 2018, while the agreement also includes an option for a 10 year extension.
The gas will be exported from the Sabine Pass liquefaction plant, located in the US, while the exported gas will be about 1.75 million metric tonnes per annum (mmtpa).
Centrica will export gas from the fifth LNG train of Sabine Pass to meet gas demand of about 1.8m UK homes.
As part of the deal, Centrica will buy LNG on a Free on Board basis, which will allow it to take the cargoes for a purchase price determined by the Henry Hub natural gas price.
Centrica chief executive Sam Laidlaw said the contract enables the company to enhance its position along the gas value chain and to ensure UK’s future energy security.
"We are therefore very pleased to have signed this agreement and look forward to working with Cheniere," Laidlaw added.