Preparatory work ahead of the construction of the South Stream pipeline could be completed by the fall of 2010, Russian First Deputy Prime Minister Viktor Zubkov said on Saturday.

The South Stream project, designed to annually pump 31 billion cubic meters of Central Asian and Russian gas to the Balkans and on to other European countries, involves Bulgaria, Serbia, Hungary, Italy and Greece.

The pipeline's capacity could be eventually increased to 63 billion cubic meters annually.

"By September-October, exploratory work will be completed, and all the documentation may be ready to allow us to begin work on South Stream by the autumn," Zubkov told journalists in Berlin.

The gas pipeline is expected to start operating in late 2015. The project is part of Russia's efforts to cut dependence on transit nations. It is a rival project to the EU-backed Nabucco, which would bypass Russia.

BERLIN, January 16 (RIA Novosti)