- Russia has started delivery of the much awaited S-400 missile system for deployment on schedule this year.
- India had bought the system for over US$ 5 billion in 2018, in a deal that became contentious amid a threat of sanctions from the US on countries engaging in defence deals with Russia.
- The S-400 is among the most advanced air-defence systems in the world, with a range of around 400 km. It is capable of protecting its air defence bubble against rockets, missiles, cruise missiles and even aircraft.
