These will be units 5 and 6 of Kudankulam nuclear power plant.
The governments of India and Russia have signed an agreement on the construction by Russian nuclear engineering company Atomstroyexport of two new reactors - units 5 and 6 - at the Kudankulam nuclear power plant (KNPP) in Tamil Nadu in southern India, according to Enerdata. Russia will also lend US$4.2bn over a 10-year period to finance their construction.
Here's more from Enerdata:
The KNPP will consist of up to eight nuclear reactors of 1,000 MW each. The first one started commercial operations on 31 December 2014 and the second one in April 2017. India and Russia have already signed an agreement to build the second phase of the project (units 3 and 4) at a cost of Rs 33,000 crore (US$5.25bn).
The units entered the construction phase in October 2016 and are expected to be commissioned in 2022 and 2023, respectively. Four additional 1,000 MW reactors are also under consideration and, under the terms of this new agreement, Russia will build units 5 and 6.