The German government has taken the first formal step towards gas rationing as it braces itself for a potential halt in deliveries from Russia due to a dispute over payments.

Robert Habeck, economics minister, on Wednesday morning, activated the “early warning phase” of an existing gas emergency law put in place to deal with acute energy shortages.

The move was triggered by German concern that Russia might cut supplies to the country and its neighbours because they are rebuffing Moscow’s efforts to force payment for gas imports in roubles.

Russian officials said on Tuesday that Moscow would not “supply gas for free” to Europe, a day after G7 countries unanimously rejected President Vladimir Putin’s directive requiring rouble payments.

During the early warning phase — the first of three stages in Germany’s emergency response — a crisis team from the economics ministry, the regulator and the private sector will monitor imports and storage.

If supplies fall short, and less draconian attempts to lower consumption do not work, the government would cut off certain parts of German industry from the grid and give preferential treatment to households.

Volker Wieland, a professor of economics at Frankfurt University and a member of the German council of economic advisers, on Wednesday warned that a halt in Russian energy supplies would create a “substantial” risk of a recession and bring Europe’s largest economy “close to double-digit rates of inflation”.

Even without any disruptions in Russian gas supplies, Germany’s inflation rate could reach 6.1 percent this year, said the economists who advise the German government. Should energy imports from Russia be cut off, it would rise to between 7-5 and 9 per cent, the council said.

Habeck, who is also vice-chancellor, told journalists in Berlin that the step was taken in anticipation of the Russian law, which conflicts with the denomination of long-term supply contracts in euros or dollars.