The ruble is gaining back some of the ground it lost in a steep slide that brought the Russian currency's exchange rate as low as 80 per U.S. dollar this week.
The ruble was trading at about 66 per dollar at mid-afternoon in Moscow on December 17.
The recovery from the record lows it hit the previous day -- dubbed "Black Tuesday" by some in Russia -- came after the Finance Ministry said it was moving to shore it up by selling foreign currency.
Spokeswoman Svetlana Nikitina said the ministry "considers the ruble extremely undervalued and is starting to sell its leftover currency on the market."
The ruble has lost more than half its value against the dollar since the start of the year, largely due to a slump in oil prices and Western sanctions against Russia over its interference in Ukraine.
In effforts to prop up the ruble, the central bank has spent more than $10 billion from its currency reserves this month and raised its key interest rate by a 6.5 percentage points, to 17 percent, on December 15.