Vitaly Markelov, deputy chairman of the Gazprom management committee, said harsh temperatures and concerns over natural gas supplies meant Nord Stream was needed more than ever.
"The first string of Nord Stream is already operational and gas is being supplied to our European consumers via this thoroughfare," he said in a statement. "Portovaya facilities required to commission the second string of Nord Stream will be built in the third quarter of 2012."
Portovaya, along the Russian coast of the Baltic Sea, marks the starting point for the Nord Stream natural gas pipeline. Gazprom said most of the infrastructure at the Portovaya compressor station was in the process of installation.
Russia aims to diversify its European transit options through Nord Stream. The dual pipeline runs from the shores of the Gulf of Finland through the Baltic Sea to Germany.
Both lines, once fully operational this year, will transport around 1.9 trillion cubic feet of Russian gas each year to European consumers for at least 50 years.