The rouble recovered slightly against the dollar in late morning trading, after it dropped to historic lows against both the dollar and the euro.
At one point in mid-morning, it took more than 48 roubles to buy a dollar, as investors showed their lack of confidence in the Russian central bank's ability to control its currency.
On Wednesday Russia's central bank announced plans to limit its intervention in markets to a $350m (£221)-a-day currency buying programme, adding that although it was prepared to defend its currency using "one-off interventions", it will allow market forces to determine exchange rate.
That one-off intervention is looking increasingly likely. This year, the rouble has lost more than 48 per cent against the dollar after sliding oil prices added to woes already created by sanctions from Western economies. Export of crude oil is one of the Russian government's main sources of foreign currency, but the price of Brent crude has fallen on over-supply.
Yesterday Vladimir Putin appeared to accuse governments of engineering the fall, saying: "at some moments of crisis it starts to feel like it is the politics that prevails in the pricing of energy resources".
Charles Movit, a senior economist at IHS Economics, said although the central bank's strategy was aimed at ending speculative attacks, "the near-term path of the rouble will be less predictable".
The bank has reserved the right to intervene as required if it judges that financial stability is threatened, thus further increasing uncertainty. Given the challenge this creates for speculators, the rouble should soon stabilise at an exchange rate justified by market conditions, including those in the global oil market.