New Delhi, Aug. 30 -- In a significant development, the Russian side has submitted a detailed proposal to the Defence Ministry in response to the Indian tender for acquiring five more squadrons of the S-400 Sudarshan long-range air defence systems for the Indian Air Force.

The S-400 played a major role in India's success during Operation Sindoor, as it was responsible for taking out a large number of Pakistani surveillance and fighter aircraft while deterring others from even flying within 200 km of the Indian border.

"The Russian response to the Indian tender has been received, and it is being processed at the moment. The project is estimated to cost over Rs 50,000 crore," Defence sources told ANI when asked about the status of the pro...