MOSCOW (Sputnik) —Construction of the Sankt Peterburg, the lead ship of the Project 677, began in December 1997. It was introduced into the Navy for trial operations in April 2010. Two other ships of the class have already been laid down.
"The two Lada-class Project 677 submarines will be delivered as scheduled — in 2018 and 2019," the spokesman told RIA Novosti.
"Then the construction of the new non-nuclear Kalina-class submarines will be launched," he added.
Air-independent, closed cycle submarines, which usually use hydrogen-oxygen fuel cells, are quieter than conventional diesel-electric boats and do not have to surface or use snorkel tubes to breathe air, thereby exposing themselves to detection by radar and other sensors.