April 8 (Reuters) - U.S. liquefied natural gas producer

NextDecade ( NEXT ) said on Tuesday it had signed an agreement

with a subsidiary of Saudi Aramco to supply the

superchilled gas from its Rio Grande facility for 20 years.

As part of the deal, the Aramco subsidiary will purchase 1.2

million tonnes per annum of LNG from Train 4 at Rio Grande, its

fourth liquefaction facility, subject to a positive final

investment decision (FID) on it.

The United States is already the world's largest exporter of

LNG and President Donald Trump has promised to unleash American

energy by declaring an energy emergency. Growth in LNG exports

is part of that strategy.

The country exported a record more than 9 million metric

tons of LNG in March.

NextDecade's ( NEXT ) Rio Grande LNG export plant has been in

development for several years, suffering repeated delays, and

its phase 1 is now expected to reach completion by early 2029 at

an expected cost of about $18 billion.

The company made an FID to construct the first three

liquefaction trains at the project in 2023.

It said achieving a positive FID on Train 4 would be subject

to "entering into appropriate commercial arrangements and

obtaining adequate financing to construct Train 4 and related

infrastructure".

(Reporting by Tanay Dhumal in Bengaluru; Editing by Anil

D'Silva and Shilpi Majumdar)