It came as Goldman Sachs estimated that outflows from Russia had accelerated to $45 billion since the start of 2014 – up 60 percent from the first quarter of 2013.
In a note on Russia, published Friday, the bank warned that total capital outflows could hit $130 billion by the end of the year.
Goldman also slashed Russia's gross domestic product (GDP) growth forecast to 1 percent from 3 percent for 2014, arguing that economic activity would likely be "strongly affected" by the current political tensions.
"The main transmission mechanism will, in our view, work through a shock to domestic confidence, resulting in lower investment, a continuation of the de-stocking cycle and higher capital outflows," Goldman analysts led by Clemens Grafe said.
"In turn, those will lead to a tightening of domestic financial conditions. The uncertainty regarding our forecast is necessarily large."
Since the start of 2014 – during which violent protests led Ukraine's former president Viktor Yanukovich to flee the country, and Russia to send troops into the Crimea region - the MICEX has fallen over 18.5 percent.
(Read more: Ukraine PM: Crimea vote is a foregone conclusion)
Investors' current concerns are focussed on Sunday's vote, when the people of Crimea will decide whether to remain part of Ukraine.
They are widely forecast to reject Ukrainian rule – but officials from Ukraine, the European Union and the U.S. have described the upcoming vote as illegal.
The real tension now lies with whether Russia decides to enforce the referendum results with military action or an immediate annexation of Crimea.
(Read more: Why Crimea matters)
Russian stocks have also been hit over recent days by concerns about a slowdown in Chinese growth, which has hurt risk appetite and seen investors flock to safe havens like gold, which hit fresh six-month highs on Friday.
The ongoing tensions have also hit Russia's currency. On Friday, the dollar was around 0.2 percent higher against the ruble, and since the beginning of 2014, the dollar has gained over 11 percent against the battered currency.
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