Italy hosted a board of directors meeting for South Stream partners. Representatives from Gazprom, Italian energy company Eni, utility Electricite de France and Germany's BASF met to adopt final investment decisions for offshore sections of the pipeline.
"The South Stream project makes a great contribution to ensuring the European energy security. It allows creating alternative and reliable routes of natural gas supply to our consumers," said Gazprom Chief Executive Officer Alexei Miller.
Recent weeks have seen Hungary, Serbia and Slovenia adopt final investment decisions for their sections of the pipeline. Miller said the Italian decision marks the beginning of the project's realization.
South Stream is meant to add diversity to Gazprom's export options to Europe, which relies on Soviet-era transit systems in Ukraine.
The offshore section of South Stream will run about 575 miles through the Black Sea. It's designed for 2.2 trillion cubic feet of natural gas.
The Bulgarian government, one of the last holdouts and, was reported by Bloomberg News to have signed an investment deal Thursday with Gazprom on the pipeline. Construction on the offshore section pipeline, however, should begin in December.