"We in Russia believe that we must keep careful track of liquidity," Putin said in his first comments on a market slide that has erased a year of stock gains and renewed concerns about the country's dependence on the global price of oil.

"The finance ministry and the central bank are monitoring the situation and if necessary will use various channels to add liquidity to the market," said Putin.

He provided no details about the nature of the possible interventions and neither the finance ministry nor the central bank issued an immediate explanation.

But Putin said the finance ministry had placed 40 billion rubles ($1.35 billion) on the Moscow market on Tuesday and was primed to offer more soon.

Moscow's main MICEX index moved into positive territory after Putin's comments and ended the day down a fraction at 1,497.81 after erasing a loss of more than five percent.

The smaller RTS exchange clawed back an eight percent morning decline to finish 2.9 percent lower.

Putin -- Russia's effective leader who may return to the Kremlin in presidential elections next year -- had earlier accused the United States of acting as a "parasite" by accumulating debts that threaten the global financial system.

Yet Russia remains particularly vulnerable to global risk aversion because its economy relies heavily on revenues from oil and gas exports while its own market is still too nascent to sustain independent growth.

Renaissance Capital said a $15 per barrel drop in oil can crimp Russia's GDP growth by 1.2 percent, and more bad news came on Tuesday when the OPEC group of petroleum exporting countries lowered its demand forecast for this year and next.

Putin hinted of the alarm spreading in government by holding an unannounced meeting with the head of Russia's number two bank VTB and getting a more detailed account of how the crisis could impact Russia's financial sector.

"We feel that this is a problem that we will be able to handle," VTB chief Alexei Kostin told Putin in televised remarks.

"We are ready to withstand this much better than we were two years ago," Kostin said.

The stock slide has been accompanied by an accelerating depreciation of the Russian ruble and predictions that the central bank may have to intervene to stave off a currency collapse that badly hurt consumers in 2008-2009.

The ruble dropped about 2.7 percent against both the dollar and the euro to cap a miserable two weeks in which it has lost nearly 15 percent of its value.

Putin's comments suggest that the central bank will intervene to interrupt this slide should it go on.

But some analysts agreed with Kostin and noted that Russian businesses had learned from mistakes of the past by keeping their foreign currency debts to a minimum and relying on the local bond market for help.

"To a large extent, the significant demand for hard currency on the Russian local market in autumn 2008 can be explained by the high level of Russian companies' dollar-denominated debts," VTB Capital said in a research note.

"Since then we have seen a de-leveraging process, and most corporate borrowers have recently preferred the domestic bond market as a cheaper alternative to external borrowing."