India and Russia on 31 July signed three contracts for priority design work and supply of main equipment for units 5 and 6 of the Kudankulam NPP in Tamil Nadu. The contracts were signed between the  Nuclear Power Corporation of India Ltd (NPCIL) and Russia's JSC Atomstroyexport (part of state nuclear corporation Rosatom).

"The project for construction of units 5 and 6 of Kudankulam NPP is moving to the practical implementation phase," said Andrey Lebedev, Atomstroyexport Vice-President for projects in Southern Asia.  According to the ASE Group statement, Rosatom and Russia's economic and finance ministries approved the agreements for the third stage of the project on 17 July, and NPCIL's board of directors gave its approval on 19 July.

India and Russia signed the General Framework Agreement and credit protocol for Kudankulam 5 and 6 in June during summit talks in St Petersburg between Indian Premier Narendra Modi and Russian President Vladimir Putin.

The Kudankulam NPP is the result of an inter-governmental agreement signed between the former Soviet Union and India in 1988. The plant will comprise six VVER-1000 units with total capacity to generate 6000MWe.

Kudankulam 1 entered commercial operation in December 2014. Kudankulam 2 reached first criticality in May 2016 and was connected to India's power grid the following August. It reached 100% of its operating capacity in this January. NPCIL signed an agreement on 3 April provisionally accepting Kudankulam 2 from its Russian suppliers.

Phase two of the project – Kudankulam 3&4 – are to be built at the site and first concrete was poured for these units on 29 June marking the formal start of construction.