The ruble firmed against the euro on Monday while trading little changed against the dollar, in a week when companies' need for rubles to settle end-of-month tax payments should lend the Russian currency some support.
The ruble was steady against the dollar at 96.24 and had gained 0.6% to trade at 101.98 versus the euro.
On global forex markets, the euro was at its weakest since March 16 against the dollar, reflecting views that the European Central Bank is unlikely to raise rates further, whereas the Federal Reserve set out a hawkish rate outlook last week.
Last week, Russia's government said a new set of export duties linked to the ruble-dollar exchange rate would be introduced on Oct. 1 and last until the end of next year.
The move should lead to extra government revenues - as much as 600 billion rubles ($6.23 billion) per year, according to seven Reuters sources - and could also buttress the ruble.
The government said the duty would not apply if the ruble strengthened beyond 80 to the dollar. Otherwise it would range from 4% to 7%, reaching its maximum if the ruble was weaker than 95 per dollar.
Russian stock indexes were lower, with the dollar-denominated RTS index down 0.5% to 995 points and the ruble-based MOEX Russian index down 0.4% at 3,036.