Sukhoi's civil aircraft division has disclosed that the Superjet 100 programme is labouring under a debt of Rb70 billion ($2.1 billion) but insists measures are being discussed to ease the burden.
The airframer has produced 10 Superjet 100s so far this year, of which three have been delivered, and is expecting total production of 26 aircraft during 2013.
Sukhoi adds that it will produce 40 of the type next year.
But it notes that the company's financial performance is being "dictated" by matters such as the "significant" discounting of aircraft sold to launch customers.
Loans to the company in US dollars and euros have resulted in a heavy exchange-rate impact of Rb3.3 billion over the first six months of the year, it says, and that interest payments on loans amounted to Rb2.2 billion.
Sukhoi says several measures are being put in place, with government co-operation, to "optimise" the airframer's financial condition. Vnesheconombank last year opened a $1 billion credit line to fund the Superjet programme.
It adds that it is analysing scenarios to restructure its debt and improve liquidity, and has been holding talks with various Russian ministries to explore possible options for developing the Superjet.