Russian President Vladimir Putin is scheduled to visit India on December 4-5 for the 23rd Annual Summit, marking his first trip to New Delhi since the onset of the Russia-Ukraine war and India's Operation Sindoor. Ahead of the visit, Congress MP Shashi Tharoor has acknowledged the strong and enduring relationship between India and Russia. The visit is expected to focus on strengthening defense cooperation between the two countries, with discussions likely to include a potential new contract for S-400 air defense systems.

India and Russia are expected to explore further collaboration on various defense projects, including Moscow's offer to supply two to three additional S-400 regiments to the Indian Air Force. This proposal comes at a time when India's military still relies heavily on Russian-origin equipment, with estimates suggesting that 60-70% of its arsenal is of Russian origin. Despite a decrease in the share of Russian arms imports over the past decade, the historical trust and interoperability between the two militaries remain crucial for India's defense preparedness.

During the summit, discussions will likely address the need for timely deliveries and maintenance support, which have become increasingly important in the evolving regional security environment.

India received five regiments of the S-400 system under a $5.43 billion defense agreement in 2018. The S-400's performance during Operation Sindoor has boosted India's confidence, leading to a request for five more units. One S-400 regiment, comprising two batteries and 16 launcher vehicles, is already in India's possession.

Russia is also reportedly preparing to offer India the S-500, a next-generation missile defense system that is more advanced than the S-400. Unlike the S-400 deal, the S-500 could potentially be built with India's cooperation, involving Indian defense companies working alongside the Russian firm Almaz-Antey. The S-500 has a longer range (500-600 km) and can intercept targets at a higher altitude (180-200 km) compared to the S-400 (400 km range, 30 km altitude). While the S-400 is designed to destroy fighter jets, cruise missiles, and drones, the S-500 can also intercept ballistic missiles and hypersonic weapons.

Operation Sindoor in May highlighted the effectiveness of the S-400, which is known as the "Sudarshan Chakra" in India. An S-400 unit based in Adampur reportedly shot down a Pakistani aircraft at a range of 314 km. The Indian Air Force confirmed that the system neutralized seven Pakistani aircraft and tracked over 300 airborne targets simultaneously. The S-400's rapid deployment capability, which is under five minutes, has been highlighted as a key tactical advantage.

The integration of the S-400 into India's multi-layered air defense grid along the China and Pakistan borders has been widely regarded as a force multiplier, enhancing the country's strategic autonomy.

India is also planning to discuss additional surface-to-air missiles for the existing S-400 units, with the IAF assessing the system's performance during Operation Sindoor as "exceedingly well". A separate proposal for S-400 missiles with interception ranges of 120 km, 200 km, 250 km, and 380 km, aimed at replenishing stocks and strengthening reserves, will also be under discussion.

In addition to the S-400 discussions, India is likely to push for a Rs 63,000 crore plan to modernize its Sukhoi-30MKI fleet. This upgrade will include new radars, avionics, long-range weapons, and multi-sensor fusion to extend their combat relevance. While the modernization will be led domestically, Russia is expected to contribute in select areas.

The last two S-400 squadrons from the 2018 deal are expected to be supplied by November 2026, following delays related to the Ukraine conflict. The Defence Ministry has reportedly agreed to a Rs 10,000 crore order for additional S-400 missiles to ensure replenishment and reserve creation.

Despite India's increasing focus on domestic defense manufacturing under the 'Aatmanirbhar Bharat' initiative and its growing arms partnerships with France and the United States, collaborations with Russia such as the S-400, BrahMos cruise missile, and T-90 tanks, continue to be vital.