In an arms acquisition, India announced that it will buy the S-400 'Triumf' air defence systems from Russia which is worth over $5 billion.
India would also collaborate in making four states of art frigates besides setting up a joint production facility for making Kamov helicopters.
The deals were announced following talks held between Prime Minister Narendra Modi and Russian President Vladimir Putin on the sidelines of the BRICS Summit.
The development comes as Russia hopes to stave off tough competition from the Americans and the Europeans to continue being India's foremost defence supplier.
The most strategically important decision is the inter-governmental agreement for the purchase of S-400 'Triumf' long-range air defence missile system which has the capability to destroy incoming hostile aircraft, missiles and even drones at ranges of up to 400 km.