Russian energy company Gazprom said the last sections of the second string of the Nord Stream natural gas pipeline were connected at Portovaya Bay in late August.
"The completion of Phase 2 will be affirmed soon," Russian President Vladimir Putin was quoted by ITAR-Tass as saying. "A ceremony has been scheduled for Oct. 8 to start up the second line of the gas pipe."
Both lines, once fully operational, will transport about 1.9 trillion cubic feet of Russian gas each year to European consumers for at least 50 years.
The system is part of a network of pipelines planned by Gazprom to diversify Russian natural gas exports to European consumers. The first leg of the pipeline system went into service last year.
The European Commission announced recently it launched an anti-trust investigation into Gazprom's practices in the region. European leaders have embraced their own network of gas transit projects, the Southern Corridor, in an effort to break the Russian grip on the regional energy sector.