HOUSTON, May 2 (Reuters) - Long-term liquefied natural gas (LNG) contracts ramped up further as sanctions on Russian fuel squeeze an already tightly supplied market and increase global demand for U.S. LNG.

Pipeline and terminal operator Energy Transfer LP and LNG developer NextDecade Corp both announced new LNG supply agreements on Monday for customers in Europe and Asia.

The U.S. has committed to deliver additional LNG to European countries to contribute to slashing gas imports from Russia following its invasion of Ukraine.

Energy Transfer said its LNG unit has agreed to supply 2 million tonnes per annum (mtpa) of LNG from its proposed Lake Charles, Louisiana, project to the Singapore unit of trading house Gunvor Group Ltd.

The supply deal is for 20 years and first deliveries are expected to begin in 2026, the U.S. pipeline company added.

The companies did not disclose the purchase price, but said it is indexed to the Henry Hub benchmark plus a fixed liquefaction charge.

NextDecade signed a 15-year supply agreement with French energy group Engie SA for 1.75 mtpa of LNG.

The LNG will be supplied from NextDecade's Rio Grande LNG export project in Brownsville, Texas, and first deliveries are expected to begin in 2026, the company said.

The companies did not disclose the purchase price. (Reporting by Marcy de Luna; editing by John Stonestreet)