Russian lessor Sberbank intends to take 20 Irkut MC-21 narrowbodies and a similar number of Sukhoi Superjet 100 regional airliners.
Preliminary agreements have been signed with the respective airframers at the MAKS air show.
The Irkut deal has a potential list-price value of $1.7 billion. Deliveries of the MC-21s would start in 2019 and run until 2025.
The tentative pact with Sukhoi, meanwhile, would be worth $0.7 billion at list prices. It sets out parameters for a contract to be struck later this year, and follows a deal - signed earlier at the show - under which Sberbank and Sukhoi are to set up a leasing joint venture.
Sberbank has yet to find lessors for the MC-21s or Superjets.