Danish authorities approved last Thursday an operations permit for an underwater pipeline aimed to transport natural gas from Russia to Germany.
The Danish Energy Agency said its decision related to the "commissioning and operation of the Nord Stream 2 pipelines."
Last year, the agency issued a permit allowing Nord Stream 2 AG to construct the twin pipelines that were to run 147 kilometres on the Danish continental shelf, south-east of the Baltic Sea island of Bornholm.
Russian state-controlled energy company Gazprom controls Nord Stream 2 AG.
Construction of the Nord Stream 2 pipeline is nearly complete. It would double Russian deliveries of natural gas to Germany, Europe's largest economy.
The twin pipelines were to run about 1,200 kilometres through the Baltic Sea from Russia to Germany.
The pipeline also passes through Russian, Finnish, Swedish and German waters before making landfall in Germany.
The project has been criticized by the United States and some Eastern European countries, and has come under increased scrutiny following the recent poisoning of Russian dissident Alexei Navalny.
An initial Nord Stream project, also consisting of twin pipelines, went online in 2011-12.