Russia's S7 Airlines is expecting an initial iteration of Sukhoi's Superjet 75 to emerge before the end of this year.
S7 has reached a preliminary agreement to acquire 50 of the proposed 75-seat aircraft, also known as the SSJ75, and is acting as a technical advisor for the project.
It says that, once the "draft" of the new aircraft is submitted, a decision on further co-operation will be made within three months.
"The Russian market needs an efficient aircraft that meets flight, technical, environmental and economic requirements," says S7 Group chief Anton Eremin.
He wants Sukhoi's civil aircraft division to present a "modern and competitive" jet to the market.
"If the project is successfully completed, we will be happy to become the initial customer of the SSJ75," adds Eremin.
S7 is not a Superjet operator but it has moved into the 75-seat sector with the introduction of Embraer 170s to enhance its regional network.
It says the development of the SSJ75 will involve a "comprehensive upgrade" of the current Superjet 100.