Ukraine’s gas grid operator says it is cutting Russian gas flowing to Europe through two key sections of its pipeline network from Wednesday, citing “force majeure” because of interference in its operations by occupying forces.

GTSOU said the two sections it would shut down, which are currently in the hands of Russian troops, are handling a third of Russian gas flowing to Europe through the country. “The interference of the occupying forces in technical processes and changes in the modes of operation of GTS facilities, including unauthorized gas offtakes from the gas transit flows, endangered the stability and safety of the entire Ukrainian gas transportation system,” the operator said.

The Ukrainian operator said it would temporarily shift capacity to another entry point to ensure continued gas flows to Europe. However, Russian gas export monopoly Gazprom told state-owned news agency TASS it would be “impossible” based on the Russian flow scheme.

“They are lying,” a spokeswoman for Ukraine’s energy ministry said.