Russian gas giant Gazprom will completely shut down the Nord Stream pipeline, until a turbine is repaired - even though services were due to resume on Saturday after a maintenance operation.
In a statement, Gazprom said it had discovered "oil leaks" in the turbine during the maintenance tasks, and that "until the repair (...) the transport of gas via Nord Stream is completely suspended."
Gazprom said it had discovered the new problems during a technical inspection with representatives of the German group Siemens, which manufactured the turbine.
The Russian group reports the oil leak is affecting "cables connected to speed meters of a rotor." On Telegram, the group posted a photo showing cables surrounded by a brownish liquid.
Earlier in the day, the Kremlin said the operation of the Nord Stream pipeline was "threatened" by a shortage of spare parts due to sanctions targeting Moscow for its offensive in Ukraine.
Since the start of the Kremlin's military intervention in Ukraine in late February, Moscow has sharply reduced its gas supplies to Europeans in response to massive Western sanctions.
European countries, some of whom are heavily dependent on Russian gas, accuse the Kremlin of using it as a means of pressure, which Moscow refutes, citing technical problems caused by the sanctions or delays in payment.
What has some of the reaction been?
Before the invasion of Ukraine, Germany had traditionally been one of the biggest importers of Russian gas, but said on Friday its supplies were secure, despite the Gazprom shutdown.
"The situation on the gas market is tense, but the security of supply is guaranteed," said a spokeswoman for the German Ministry of Economics in a statement.
Without commenting on Gazprom's announcement, the spokeswoman said Germany had "already seen Russia's unreliability in recent weeks."
To compensate for the missing gas supplies, European countries have been trying to find other suppliers and reduce their consumption against a backdrop of skyrocketing gas prices on the markets and the possibility of a recession.
A total cut-off from Russian gas could cut French growth by one point, said the Minister of the Economy, Bruno Le Maire.