India’s plan for 5 more S-400 systems gains momentum, Russia sends cost details

India’s plan to acquire five additional S-400 Triumf air defence systems from Russia has moved forward, with Moscow sending a Bill of Quantities (BOQ) proposal to New Delhi. The document details construction and material costs and is expected to form the basis for negotiations over the price of the proposed deal.

The development comes months after Operation Sindoor, during which the S-400 system played a key role in India’s air defence operations, according to sources cited in the report.

Cost negotiations to decide next step

India is yet to formally approve the additional systems. The proposal will have to go through cost negotiations with Russia before being considered by the Cabinet Committee on Security.

A clearance from the finance ministry will also be required before the acquisition can move ahead.

The final S-400 system from the five units India ordered from Russia in 2018 for USD 5.43 billion is scheduled to arrive in November this year.

One of the five additional systems is expected to be positioned in India’s eastern sector, facing China.

S-400 performance highlighted after Operation Sindoor

The Russian-made air defence system came under focus during Operation Sindoor in May 2025. According to the report, an S-400 long-range missile struck a Pakistani early airborne warning aircraft at a distance of 314 kilometres across the Indus.

The report also said Pakistan used kamikaze drones in attempts to target S-400 units stationed at Adampur and Bhuj air bases. The air defence system, along with the Akash Tir system, was credited with keeping Pakistani fighters away from Indian airspace.

According to the report, Pakistan subsequently moved its air assets to bases near the Durand Line after Indian strikes hit 11 of its air bases.

No decision yet on Su-57 purchase

While reports have suggested that India could acquire two squadrons of Russia’s fifth-generation Su-57 fighter aircraft, the report said no decision has been taken on the proposal.

The Indian Air Force has, however, shown interest in the Russian offer amid the deployment of Chinese J-20 fifth-generation fighters at airbases in Tibet.

With Russian President Vladimir Putin expected in Delhi for the BRICS summit from September 11 to 13, defence cooperation between the two countries is also expected to feature in discussions, including the hypersonic missile sector.