MOSCOW (Reuters) – The rouble hit a one-week low past 93 to the dollar on Monday as the Russian market reopened after a deadly shooting rampage near Moscow on Friday evening, with the Russian currency supported by high oil prices and month-end tax payments.

Russia lowered flags to half-mast for a day of mourning and charged four men it accused of gunning down scores of people at a concert outside Moscow on Friday night in the deadliest attack inside Russia for two decades.

At 0730 GMT, the rouble was unchanged against the dollar at 92.81, having dipped to a one-week low in early trade. It had lost 0.1% to trade at 100.36 versus the euro and shed 0.3% against the yuan to 12.78.

Investors were also reacting to Friday’s interest rate hold at 16%. The Bank of Russia warned that inflationary pressure remained high and that tight monetary conditions would be maintained for a long time to try to return inflation to the bank’s 4% target.

, a global benchmark for Russia’s main export, was up 0.4% at $85.76 a barrel.

The rouble should also be supported this week by month-end taxes that usually see exporters convert foreign currency revenues to pay local liabilities.

Russian stock indexes were lower.

The dollar-denominated RTS index was down 0.5% to 1,107.0 points. The rouble-based MOEX Russian index was 0.4% lower at 3,259.5 points.

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