Korean shipbuilder DSME has firmed up an order by Pantheon Tankers-linked Alpha Gas for two LNG carriers.
The yard said the 173,400-cbm ships are costing $370m combined.
Delivery will be by the end of 2020.
The vessels have ME-GI engines and a rull re-liquefaction system.
TradeWinds understands the newbuilding contracts were arranged by Arrow Shipping in London.
DSME claims to be able to boost fuel efficiency by 30% and cut emissions by the same amount through its technology.
A yard spokesman said: "We see positive signs as the market is improving compared to last year and ship prices are rising.
