The S-500 missile defence system and Su-57 stealth fighter are emerging as key defence discussions between Prime Minister Narendra Modi and Russian President Vladimir Putin on the sidelines of the SCO Summit, as India looks to expand its military cooperation with Moscow, according to a TOI report.
The talks come after the S-400, deployed during Operation Sindoor, reportedly demonstrated its capabilities against aerial threats, strengthening the case for adding newer Russian systems to India’s defence arsenal.
The S-400, which is designed to provide theatre-level air defence with a reach of up to 400 kilometres, was reportedly effective in detecting and countering aerial threats during Operation Sindoor. Its reported performance has added momentum to discussions about adding capabilities that could address threats beyond the system’s primary role.
India currently operates four S-400 squadrons out of the five ordered under a $5.43 billion contract signed in 2018. The four systems have been deployed across the country’s western, northern and eastern fronts, and their reported performance during Operation Sindoor has added attention to the platform.
The fifth and final squadron from the original order is scheduled for delivery by November 2026. India is also moving towards expanding the fleet, with the Defence Ministry clearing a proposal for five additional S-400 squadrons worth more than Rs 50,000 crore. Russia has submitted its bid for the proposed acquisition, which could also include local co-production.
The S-400 and S-500 are not intended to perform exactly the same role. As reported, the S-400 is designed primarily as a theatre-level air-defence system, with an interception range of up to 400 km, while the S-500 Prometheus is being positioned as a higher-tier shield against ballistic missiles and hypersonic threats.
The S-500 is reported to have a maximum interception range of around 600 km and an engagement altitude of about 180 to 200 km, taking its operations into the near-space layer. Its reported reaction time is around three to four seconds, compared with roughly nine to 10 seconds for the S-400.
The systems also differ in the types of threats they are designed to tackle. The S-400 is intended to engage threats including stealth aircraft, cruise missiles, drones, bombers and tactical ballistic missiles. The S-500, meanwhile, is reported to be capable of targeting more advanced threats, including intercontinental ballistic missiles, hypersonic glide vehicles and potentially low-Earth-orbit satellites.
The two systems would therefore work as part of a layered defence network rather than one replacing the other. In this arrangement, the S-500 would form the outer layer, using its longer-range and higher-altitude capabilities to engage ballistic and hypersonic threats, while the S-400 would provide the lower atmospheric layer against aircraft, drones and cruise missiles that enter its operational envelope.
The S-400 uses 48N6-series and 40N6E interceptors, while the S-500 is associated with the 77N6-N and 77N6-N1 hit-to-kill interceptors. As reported, the S-500 is also designed with a low-Earth-orbit anti-satellite capability, giving it a role extending beyond conventional air defence.
This distinction is important to the India-Russia discussions because the S-500 would not simply duplicate India’s existing S-400 capability. Instead, it could add a higher-altitude layer to the air-defence architecture while allowing the S-400 to continue handling conventional aerial threats.
Another potential difference from the earlier S-400 arrangement is the proposed industrial structure. Rather than simply purchasing the system, India could explore a co-production model involving an Indian partner and Russian defence industry, according to the New Delhi-based think tank India Foundation.
Russia has been promoting the S-500 to India for several years. In 2021, then Russian Deputy Prime Minister Yury Borisov said India could potentially become the first foreign recipient of the missile defence system.
Any agreement would still require discussions on technical specifications, manufacturing arrangements, costs and logistics before moving forward.
The Russian Su-57 stealth fighter is another major platform linked to the Modi-Putin discussions.
Kremlin spokesperson Dmitry Peskov has backed the aircraft’s capabilities, calling it one of the best fighter jets in the world and confirming that the aircraft was being discussed with India.
Russian officials have also raised the possibility of producing the aircraft under licence in India and integrating Indian-origin weapons onto the platform. Such cooperation could build on existing defence projects between the two countries, including BrahMos.
For India, the timing is linked to an urgent requirement for additional fighter aircraft.
The Indian Air Force is dealing with a shortage of combat aircraft, with its squadron strength at a six-decade low. At the same time, China is expanding its fifth-generation fighter fleet and testing sixth-generation aircraft.
India’s own fifth-generation fighter programme is not expected to enter service before 2035, according to the information provided, creating pressure for an interim capability as the regional air power balance changes.
The Su-57 could therefore offer India a possible fifth-generation option while its indigenous programme continues to develop.
The S-500 and Su-57 were absent from the joint statement issued after the Indo-Russian Summit in December last year. Critical technical, financial and logistical questions had remained unresolved, according to reports.
India’s continued acquisition of Russian military equipment also remains a source of concern in Washington, adding another strategic consideration to any future agreement involving either platform, reports TOI.
Putin is scheduled to travel to India later this month for the BRICS summit, providing another potential opportunity for the two sides to advance discussions.
The talks are also understood to extend beyond the S-500 and Su-57.
India and Russia have reportedly discussed expanding logistics cooperation through reciprocal access to military facilities. Another potential area is a major upgrade for India’s Sukhoi-30MKI fleet, including improvements to radars, avionics and weapons systems.
The objective of the upgrade would be to extend the aircraft’s service life while improving its operational capability and lethality.
Together, the discussions indicate that India’s defence engagement with Russia is looking beyond individual weapons purchases, with air defence, fighter aircraft, industrial cooperation, logistics and fleet modernisation forming part of a broader military relationship.
