South Korea's Samsung Heavy Industries (SHI) has won a newbuilding contract worth $1.7bn for seven shuttle tankers.
In a regulatory filing the yard said it had struck a deal with a company from "Eurasia" to supply design, blocks and parts for the vessels. Further details were not disclosed.
Shipbuilding sources said the high contract value indicates the vessels will be used for the Russian Arctic. They believe the yard has clinched the contract from Russia's Rosneft.
"The deal is related to the joint shuttle tanker venture that Samsung formed with Zvezda shipyard in 2019," said a source.