One of the biggest Indian defence deals with Russia worth around $25 billion for 127 fifth generation fighter aircraft (FGFA) might not see the light of the day as the Indian Air Force (IAF) has cited differences with Russia, flagging at least 15 objections to the programme, the New Indian Express reported.

The report notes of an internal communication letter that was sent to the ministry of defence from air headquarters in March 2016 with at least 15 objections in the Indo-Russian project to co-develop India's FGFA. The letter shows how the IAF is critical of the project, which can be unsafe for its pilots in future. Only some objections have been leaked out to the media, including those that state the current FGFA project has unreliable engine, poor stealth features, deficient radar and cost over-run.

A highly placed source told the publication that "only a political call" can save this project.

The report also mentions that the IAF has been wary of Russia not offering its pilots access to the developed prototypes (Sukhoi T-50 PAK-FA).

It is important to know that New Delhi too is equally bearing the project cost for its preliminary design. India has already spent Rs 1,500 crore on the programme.

As per an inter-governmental agreement (IGA), the Hindustan Aeronautics Limited (HAL) is the implementation organisation from the Indian side, but the IAF is apprehensive about Russia not being eager to share the critical design work.

The next step in the programme is the signing of the $6 billion research and development contract, which will need India to fund an additional $6 billion, a move that will need Defence Minister Manohar Parrikar to take a call during the Defence Acquisition Council meeting.

The IAF has its own issues, given the fact that the current NDA government cancelled the Medium Multi-Role Combat Aircraft (MMRCA) tender for 126 aircraft and opted for 36 Rafale jets instead. The IAF is reeling under the problem of depleting fighter squadrons strength from the authorised 42 to current 34, it could take about eight years for delivery of FGFA to IAF from the start of the research and development contract, the report noted.