Russian companies will sign three key agreements with Nuclear Power Corporation of India Ltd for Kudankulam units 5 and 6, by the end of this month, said Sergey Orlov, who heads the India operations of Atomstroyexport, one of the Russian companies engaged in the construction of nuclear power projects.The ‘long manufacturing cycle equipment and first priority equipment agreement’ would give the go-ahead to the Russian companies to begin production of key equipment such as reactor pressure vessels and steam generators, which take long time to manufacture.The other two agreements are called ‘first priority designing’ and ‘contract for working documentation’ and are, like the first agreement, essential foundational agreements for starting the projects. The three agreements follow the signing of the ‘general framework agreement’ between NPCIL and its Russian counterpart, Rosatom, on June 1, 2017. Addressing journalists here, Orlov said Russia’s intention was to “start construction work on one unit each year” for the next four years.