NEW DELHI — Just when its production was about to take off, the Indo-Russian fifth-generation fighter aircraft appears to be "lost" because Russians are demanding an "unaffordable price for the aircraft," according to a senior Indian Air Force official.

The Russians are demanding more than $7 billion as part of India's share in the development of the FGFA. The Russian side argues that the higher price is justified because the aircraft's development will include transfer of technology of several high-tech systems.

"India is not in a position to pay this kind of money, and the aircraft project appears to be lost " the official said.

The Indian version of the FGFA, known as the Perspective Multi-role Fighter, is being jointly designed and developed by India and Russia. State-owned Hindustan Aeronautics Limited from the Indian side and Rosoboronexport from Russia are the designated lead agencies.

India and Russia agreed to jointly build the FGFA in 2007 and signed an initial development agreement in 2010. The final agreement, which has not yet been inked, will release India's share of development cost for the FGFA project.

In early 2016, an internal report by the Indian Air Force listed several drawbacks of the proposed FGFA with Russia, including the engine, stealth capabilities and an expensive radar.

According to the report, there are about 40 parameters related to the aircraft that require improvement, which the Air Force had wanted the Russians to meet. These include better stealth, AESA radar, advanced sensors, networking and combat avionics, and supercruise.

After the Air Force report, Ministry of Defence officials here were quick to say that despite the shortcomings, solutions are being worked out and the FGFA project is on track.

The FGFA has a potential order by the Indian Air Force worth more than $25 billion.

The service has a requirement for 120-130 swing-role planes with stealth features for increased survivability, advanced avionics, smart weapons, top-end mission computers and 360-degree situational awareness. The ability to supercruise or sustain supersonic speeds in combat configuration without kicking in fuel-guzzling afterburners is a key Indian requirement, according to another Indian Air Force official.

The Russian side is moving ahead with its FGFA version known as T-50. The first flight of a T-50 took place in 2010, and induction is scheduled this year. Russia announced it will fly the T-50 with an advanced engine, giving it Mach 1.5 supercruise, by 2020.

The Russians are developing the FGFA in response to the American F-22 Raptor and F-35 Lightning aircraft.

Vivek Raghuvanshi is the India correspondent for Defense News.

More In Air Warfare