In 2015, Moscow and New Delhi had agreed to perform design work in India on a fifth-generation version of the Su-35 called Su-35S. China had also been negotiating for 24 Su-35s then. But whereas China has signed up to purchase those aircrafts, India signed for Rafales.
Still more, whereas China’s Su-35 is slightly advanced (4th generation plus) than legacy Su-35 (4th generation), India’s Su-35S (5th generation) was supposed to be much more advanced with stealth properties.
Russia had quoted the price of $85 million per aircraft. Rostec CEO Sergey Chemzov was quoted during the IDEX show in Abu Dhabi, ” We (Russia and India) have been negotiating and have signed the intention protocol for the Su-35.”. Rostec is Russia’s state-run corporation that oversees export of high-tech products.
However, a Dassault Aviation spokesman when asked about the Indian agreement for design work on the Su-35S, said the Indian Air Force chief (Anup Raha, then) has said a Sukhoi cannot replace a Rafale.
Russian aircraft makers had been more than willing to step in and fulfill IAF’s needs for two reasons. First was apparently economic. Secondly, Russia wanted to undercut France as punishment for Paris refusing to deliver two Mistral helicopters carriers to Russia amid deepening tensions with Ukraine.
Besides, Russia had offered an upgraded version of Mig-35, if India reopened the tender.