The dollar-denominated RTS index had dropped by 4.16 percent as of 0725 GMT, while Russia`s battered ruble fell to 76 against the dollar and over 83 against the euro for the first time since the currency slump of December 2014.
Russia`s economy and the ruble have been battered since 2014 by the slide in oil prices and Western sanctions over Moscow`s role in the Ukraine crisis.
But the continued slump in oil prices, with Brent crude trading below $33 on Monday, and worries over the state of China`s economy pummeled Russia`s markets and currency as trading began again following a break for the Orthodox Christmas last week.
Analysts warned that if the price of oil continues to fall then that could mean even more trouble for Russia`s economy just as officials were claiming that it was edging out of recession.
"If oil prices keep dropping, the ruble could have to continue to adjust itself," analysts from the VTB Capital said.
The World Bank has said that the full-year downturn for 2015 could have reached 4.3 percent, given the low oil price, and that Russia is likely to remain in recession for all of 2016.
President Vladimir Putin has assured that Russia could weather the headwinds, despite volatility in oil prices.
Moscow stock exchange drops by over 4 percent, ruble hit
11 January 2016
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The Moscow stock exchange on Monday dropped by more than four percent as Russia`s energy-dependent economy reels from low oil prices and fluctuations on the Asian market.
