Moscow's insistence on rouble payments for the Russian gas that meets a third of Europe's annual energy needs has galvanised others in Europe: Greece called an emergency meeting of suppliers, the Dutch government said it would urge consumers to use less gas and the French energy regulator told consumers not to panic.
The demand for roubles, which has been rejected by Group of Seven nations, is in retaliation for crippling Western sanctions on Russia following its invasion of Ukraine.
Russia's most senior MP said on Wednesday Russia could demand rouble payments also for other commodities including oil, grain, fertilisers, coal and metals, raising the risk of recession in Europe and the United States.
Moscow is expected to make public its plans for rouble payments on Thursday, although it said it would not immediately demand that buyers pay for gas exports in the currency.
Russian President Vladimir Putin told German Chancellor Olaf Scholz on Wednesday that nothing would change for European partners and payments would still be made in euros and transferred to Gazprom bank, a German spokesperson said.
Western countries have said payment in roubles would breach contracts that can take months or more to renegotiate, a prospect that has driven commodity prices higher.
It would also blunt the impact of Western curbs on Moscow's access to its foreign exchange reserves and bolster its currency.
The European Union is preparing more sanctions against the Kremlin, EU sources told Reuters on Wednesday, with their scope depending on Moscow's stance on gas payments in roubles.
Berlin's unprecedented move is the clearest sign yet the European Union is preparing for Moscow to cut gas supplies unless it gets payment in roubles. Italy and Latvia have already activated warnings.
German Economy Minister Robert Habeck implemented the "early warning phase" of an existing gas emergency plan, where a crisis team from the economics ministry, the regulator and the private sector will monitor imports and storage.
Habeck told reporters Germany's gas supplies were guaranteed for now but urged consumers and companies to reduce consumption, saying that "every kilowatt hour counts".
Europe faced an energy crunch even before Russian troops entered Ukraine on February 24, with European Union gas storage levels about 26 per cent of total capacity, below normal levels at this time of year.
