Ukrainian energy company Naftogaz told Bloomberg News that Russia deliveries were short by around 840 million cubic feet per day in early February when much of the region was gripped by a brutal cold snap. It denied allegations it siphoned off gas designated for Europe.
In a statement, the deputy chief executive officer for Naftogaz, Vadym Chuprun, said the Ukrainian gas transit system was reliable and plans to circumvent Ukraine won't do much to compensate for seasonal shortages.
Gazprom is sending gas through its Nord Stream natural gas pipeline through the Baltic Sea and plans to start construction on its South Stream counterpart by December. Both avoid Ukraine.
A gas row between Gazprom in Ukraine in 2009 exposed vulnerabilities in the regional energy sector when downstream European consumers were left in the cold for several weeks. Europe gets around 20 percent of its natural gas from Russia though 80 percent of that runs through Soviet-era pipelines in Ukraine.