India's air defence plans regarding the acquisition of the S-400 long range missiles, were altered after a timely intervention by then defence minister Manohar Parrikar saved the taxpayer Rs 49,300 crore for the next decade, The Economic Times reported.

According to the report, Parrikar ordered a review of the 15-year long-term plan to purchase new air defence systems up to 2027.

The S-400 missiles can bring down incoming stealth fighters and missiles at a range of 380 km.

The review, which was recently concluded, involved a technical study by the air force and an evaluation of all air defence systems in the world. The conclusion from the review resulted in the decision to cut down on purchase plans of shorter range missiles, the report added.

On Friday, the two nations signed the deals. The focus during the visit will be on the S-400 Triumf air defence missile systems agreement with a top Kremlin aide saying Tuesday that Russian President Putin will oversee the signing of the "USD 5 billion deal".

S-400 is known as Russia's most advanced long-range surface-to-air missile defence system. China was the first foreign buyer to seal a government-to-government deal with Russia in 2014 to procure the lethal missile system and Moscow has already started delivery of an undisclosed number of the S-400 missile systems to Beijing.

The S-400 is an upgraded version of the S-300 systems. The missile system, manufactured by Almaz-Antey, has been in service in Russia since 2007.

Apart from S-400 missiles, Moscow is also likely to ink $2.5 billion deal for four more Krivak/Talwar class stealth frigates for the Indian Navy. Under the agreement, two of the warships will be constructed at the Yantar Shipyard in Kaliningrad and the other two at the Goa Shipyard Limited.