The Moscow Times reports that Leonid Chugunov, a project manager at Gazprom, said construction should begin in September after the company reduced the completion timeframe by a year to December 2017.
Alexei Miller, the top executive at Russian natural gas company Gazprom, said in June that some of the feasibility studies for the pipeline would be unveiled during the third quarter of 2012.
Geopolitical issues between Ukraine and Russia prompted Russian natural gas company Gazprom to look for new routes to deliver gas to European costumers.
South Stream would divide into two pipelines -- one to Greece and the other through the Balkans -- after it passes through the Turkish waters of the Black Sea. The project would carry roughly 2.2 trillion cubic feet of gas per year when it goes into service by 2015.
Gazprom tested the first leg of the dual Nord Stream pipeline system through the Baltic Sea early this year. The Russian company said it met the basic testing criteria for industrial standards.