Finding an equilibrium level for the rouble may not be easy, as it depends on oil prices that are fluctuating, and on how quickly trade and capital outflows adjust to the new exchange rates.

The rouble has fallen roughly 33 per cent against the dollar since the end of the summer. On January 22 the central bank announced its ambition not to let it past about 36 to the dollar, or 41 to a basket of euros and dollars which is how the bank measures the rouble's value. Yesterday the rouble hit 46.29 versus the euro and 36.35 to the dollar.

Analysts are divided on the wisdom of the central bank's policy. Elina Ribakova, chief economist at Citibank's Moscow office, said the central bank might have been premature: “I don't believe in this level,” she said, “Given the costs and benefits I think they'll have to move again.