Gazprom's halt of gas transit to Hungary via Ukraine should entail sanctions against the operator of the Nord Stream 2 gas pipeline, Nord Stream 2 AG, Naftogaz Ukrainy Board Chairman Yuriy Vitrenko says.

"We are waiting for sanctions to be imposed on Gazprom's 100% subsidiary, the Nord Stream 2 operator ... The absence of efficient sanctions has led to Gazprom's expectations that it would actually be allowed to continue using gas as a weapon against Ukraine and other countries and to use Nord Stream 2 in disregard of European rules," Vitrenko said on Facebook on Friday.

The end of gas transit to Hungary via Ukraine is an illustrative demonstration of consequences of the Nord Stream 2 launch, "which creates enormous threats to Europe and Ukraine," he said.

"The Kremlin has been doing that on purpose. It's not even saber rattling, it's an obvious use of gas as a weapon," Vitrenko said, adding that the United States and Germany agreed on appropriate reactions to such Russian actions in their joint statement.

Moscow should unblock access of third parties to gas transit via Ukraine in order to minimize Nord Stream 2 influence, Vitrenko said.

Consistent with European regulations, Ukraine has provided a firm capacity for gas transportation to Hungary from Ukraine, while Hungary has not done so, he said.

"This means that gas supply to Hungary from Ukraine is guaranteed, while gas supply to us from Hungary is not. This is the kind of 'one-sided' European integration with Hungary we have now," Vitrenko said.