The almost-completed project's final major hurdle is obtaining an agreement from Denmark that the Baltic Sea pipeline can cross its exclusive economic zone, which is outside its territorial waters.
“If they don't approve it… we will go around Denmark's economic zone,” Gazprom chairman Viktor Zubkov said at a Moscow energy forum, quoted by TASS news agency.
If Denmark withholds permission, the project “will be more costly and will take longer,” he said, criticising Copenhagen's stance since the pipeline will provide “gas for Europe.”
The building of the pipeline has sparked concerns about Western Europe's increasing dependence on Russian gas.
It has also raised fears that Moscow will be able to increase pressure on Ukraine as Europe will be less reliant on the country for transiting supplies.
Its proponents — led by Germany, the EU's biggest economy — say the pipeline will provide reliable supplies at an acceptable price.
Gazprom had said in a statement on Tuesday that the pipeline is 83 percent complete, with more than 2,000 kilometres laid.
“We have practically reached… Denmark's economic zone,” Zubkov said, adding that if Copenhagen gives the green light, the project could be completed in “four to five weeks.”
Russian Energy Minister Alexander Novak at the same forum said he was still counting on Denmark granting approval.
“We don't see any basis not to give such a permit,” he said.
Half of the 9.5-billion-euro ($10.6-billion) project is financed by Gazprom, with the rest covered by its European partners: Germany's Wintershall and Uniper, Anglo-Dutch Shell, France's Engie and Austria's OMV.
US President Donald Trump has threatened to hit Nord Stream 2 and those tied to it with sanctions, saying it makes Germany “a hostage to Russia.”
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