The FSRU will function as a regasification terminal for liquified natural gas (LNG) and will be based in the Bay of Gdansk.
Poland has turned to seaborne LNG as well as gas piped from Norway via Denmark and the Baltic Sea to replace supplies from Russia.
"The selection of the supplier of the LNG regasification unit is an important milestone in the implementation of the FSRU Program, which the Company has been working on for many months," Andrzej Kensbok, vice president of the management board of Gaz-System, said in a statement.
He said the company will begin working out detailed terms for charter of the FSRU.
Mitsui O.S.K. Lines has a fleet of almost 800 ships, including seven FSRUs.
