Russia has indefinitely halted gas supplies to Germany via a key pipeline after saying on Friday it had found problems in a key piece of equipment, a development that will worsen Europe’s energy crisis.

Russian gas giant Gazprom said on Friday that the Nord Stream pipeline, which is due to reopen over the weekend, will remain closed until a turbine is repaired.

In a statement, Gazprom said it discovered “oil leaks” in a turbine during a planned three-day maintenance operation.

Gazprom added that “until repairs … gas transportation through Nord Stream is completely suspended.”

The resumption of supplies via the pipeline, which runs from near St. Petersburg under the Baltic Sea to Germany, was due to resume on Saturday.

Gazprom said it discovered the problems conducting maintenance work with representatives from Siemens, who made the turbine in a compressor station that pushes gas through the pipeline.

On its Telegram page, it published an image of cables covered in a brown liquid.

Earlier in the day, the Kremlin warned that the future operation of the Nord Stream pipeline, one of Gazprom’s main supply routes, was at risk due to a lack of spare parts.

“There are no technical reserves, only one turbine is working,” Kremlin spokesman Dmitry Peskov told reporters.

“So the reliability of the operation, the whole system, is at risk,” he said, adding that Russian energy giant Gazprom is “not to blame.”

After imposing economic sanctions over Ukraine’s invasion of the Kremlin, Russia has reduced or halted supplies to various European nations, causing energy prices to spike.

The Kremlin blames European sanctions for the reduction in deliveries via Nord Stream, which it says blocked the return of a Siemens turbine repaired in Canada.

Germany, where the turbine is now located, said Moscow is blocking the return of the critical piece of equipment.

Berlin has previously accused Moscow of using energy as a weapon.

Gazprom’s announcement comes on the same day that the G7 nations said they would work to quickly impose a price cap on Russian oil exports, a move that would deprive the Kremlin of vital revenue for its war effort.

Gazprom also announced the suspension of gas supplies to France’s main utility Engie from Thursday after the latter failed to pay for all supplies made in July.

As winter approaches, European nations have attempted to fully replenish their gas reserves, secure alternative supplies and implement plans to reduce consumption.

However, a long-term halt to Russian gas supplies would complicate efforts by some nations to avoid shortages and rationing.

Germany said on Friday its gas supply was secure despite the halt to deliveries via Nord Stream.

“The situation on the gas market is tense, but security of supply is guaranteed,” said a spokeswoman for the Ministry of Economic Affairs in a statement.

The spokeswoman did not comment on the “content” of Gazprom’s announcement on Friday, but said Germany had “already seen Russia’s unreliability in recent weeks.”

German officials have recently struck a more positive tone for the coming winter.

Before the recent shutdown, Chancellor Olaf Scholz said Germany is now “in a much better position” in terms of energy security, having met its gas storage targets much earlier than expected.

Europe as a whole has also pushed ahead with filling up its gas storage facilities, while fears of curtailed supplies have prompted companies to reduce their energy consumption.

According to the Federal Network Agency, Germany’s industry consumed 21.3 percent less gas in July than the average for the months 2018 to 2021.

Bundesnetzagentur boss Klaus Müller said that such a preventive approach could “save Germany from a gas emergency this winter”.

Europe as a bloc, meanwhile, is preparing emergency measures to reform the electricity market to bring soaring prices under control.

Fears of natural gas shortages have pushed power futures contracts to record highs in France and Germany.

European consumers also expect huge electricity bills as utilities pass on their higher energy bills.