Ukraine says it will suspend the flow of gas through a transit point that delivers almost one-third of the fuel that Russia exports to Europe across Ukraine.

GTSOU, Ukraine’s state-owned natural gas pipeline operator, said in a statement that it could not operate at the Novopskov gas compressor station due to “the interference of the occupying forces in technical processes.”

The Novopskov compressor station in the Luhansk region of eastern Ukraine has been occupied by Russian forces and separatist fighters since soon after the Russian invasion began.

The suspension, which affects gas flows via the Sokhranivka route, will take effect from May 11.

Yuriy Vitrenko, head of the state energy company Naftogaz, said gas flows to Europe via Ukraine could fall by one-third unless Russia switches to using a different route.

GTSOU declared “force majeure,” a clause invoked when a business is hit by something beyond its control.

It said the affected flow of gas could be shifted elsewhere — to the Sudzha interconnection point located in territory controlled by Ukraine. But Gazprom, which supplies the gas sent through the pipelines, said this would be “technologically impossible.”

It said it had seen no proof of “force majeure” or obstacles to continuing gas flow as before.

Ukraine has remained a major transit route for Russian gas to Europe even after Russia’s invasion began on February 24. Europe has worried since the start of the war that Russia would turn off the gas in retaliation for sanctions, but until now the gas has continued to flow.

Given the uncertainties, European countries are searching for alternative fuel supplies. Plans for the expedited construction of liquefied natural gas (LNG) terminals earned approval from the German cabinet on May 10.

The proposal is designed to make it easier to build floating and land-based LNG terminals, which would allow Germany to accept LNG deliveries by boat from non-Russian gas producers.

It allows regulators to skip processes, including those related to environmental controls, in the interest of getting the terminals constructed faster. The hope is to have the first new LNG terminal operating by year’s end.

“With this LNG expedition law, we’ll create the framework to make us independent of Russia quickly,” said Michael Kruse, a spokesperson on energy for the Free Democrats (FDP) party, a member of the current governing coalition.

The measure must be approved in both the Bundestag, the lower house, and the Bundesrat, the upper house, to become law.

Energy was among the topics to be discussed on May 10 during a meeting between Italian Prime Minister Mario Draghi and U.S. President Joe Biden at the White House. Despite Italy’s dependence on Russian gas, Draghi has pledged support for any European Union sanctions on Russia’s energy sector.