SINGAPORE -- PetroVietnam Gas has issued a tender seeking to buy Vietnam's first cargo of liquefied natural gas (LNG), sources said on Friday, marking a milestone on the Southeast Asian nation's route to becoming a key importer.

A manufacturing powerhouse that generates most of its electricity from coal, Vietnam is drafting a new power plan that aims to boost its installed LNG-fired power generation capacity to up to 24.5 gigawatts by 2030.

The cargo of 50,000 tonnes to 70,000 tonnes is sought on a delivered ex-ship (DES) basis for delivery between June 1 to July 31, the sources said, adding that the tender will close on May 11.

"We are importing this first batch to test-run the terminal before we put it into commercial operation," said one of the sources, who all sought anonymity as they were not authorised to speak to media.

The Thi Vai LNG Terminal in the province of Ba Ria Vung Tau will primarily supply two gas-fired power plants with combined capacity of 1.5 gigawatts now being built in the neighbouring province of Dong Nai by PetroVietnam Power Corp, at a cost of $1.4 billion.

The Nhon Trach 3 and Nhon Trach 4 power plants are set to start generation in the fourth quarter next year and the second quarter of 2025, respectively, according to PetroVietnam Power.

"We can supply to other clients in the area based on market conditions," said a third source familiar with the development of the terminal.

PetroVietnam Gas has said the terminal is expected to supply between 680,000 tonnes and 850,000 tonnes of LNG each year during the period from 2023 to 2027.

The latest draft of Vietnam's master power development plan aims for total installed capacity of LNG-fired power plants to range between 15.4 gigawatts and 24.5 gigawatts by 2030, or from more than 12% to more than 16% of total generation capacity.

The draft, which could still be changed, showed Vietnam would stop developing new LNG-fired power plants after 2035 and adapt some existing plants to use hydrogen.