Russia ruble declines by 3.5 pct at the opening

Russia's embattled currency, the ruble, is down 3.5 percent at the opening of trading in Moscow.

The ruble lost over 15 percent of its value this week despite Tuesday's massive interest rate hike by the Russian central bank.

The ruble has fallen sharply in recent weeks and is down more than 50 percent since January, due to sinking oil prices as well as the impact of Western sanctions imposed over Russia's involvement in Ukraine's crisis.

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