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.
Officials at Samsung were not available for comment.
Under the venture, Samsung has pledged to share its experience in the design and construction of the vessel type. It will also hand over the technical specifications and rights for the detailed ship project to Zvezda Shipbuilding Complex.
It will also help provide working design documentation together with Lazurit central design bureau.
In addition, SHI will provide technical support for planning, management, and quality control during the construction and installation works, procurement of materials and equipment, and engineering and technical assistance. It will also train Russian workers.
Shipbuilding sources said the seven shuttle tankers will each be built with capacity of 120,000 dwt.
"Samsung will be constructing up to 80% of the shuttle tankers and the remaining 20% of the ships will be finished building in Zvezda," said a shipbuilding source.
SHI is slated to deliver the half-built shuttle tankers to Russia between early 2023 and 2027. the source added.
Samsung said with the latest order, it has won a combined $10.3bn orders so far this year, surpassing its order target of $9.1 by 13%.