QatarEnergy has placed another large order for new LNG vessels as it continues to build out its shipping fleet ahead of a massive expansion in its liquefaction capacity that’s expected to come online later this decade.

The state-owned company said Wednesday it has signed a deal worth $3.9 billion to have South Korea’s HD Hyundai Heavy Industries Co. Ltd. build 17 “ultra-modern” liquefied natural gas carriers.

The agreement marks the second phase of the largest LNG ship-building program in history. Wednesday’s announcement follows a first phase order for 60 LNG tankers. Those ships are to be built at both Korean and Chinese shipyards.

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