MOSCOW Russia's central bank reduced its currency market interventions by almost half last month, selling around $3.46 billion worth of foreign currency compared to $6.1 billion in August, data showed on Wednesday.
The central bank sold $3.18 billion in dollars and 200 million euros.
The rouble firmed by 1.5 percent versus a euro-dollar basket during September, as investors scaled back bets on a near-term cut in official Russian interest rates, and took account of the postponed tapering of U.S. monetary stimulus.
The stronger rouble reduces the automatic central bank interventions that occur when the rouble is near the boundaries of a trading corridor against the basket. The central bank shifted the corridor to 32.30-39.30 roubles to the basket, as of September 30.
On Wednesday the rouble eased 0.2 percent against the basket to 37.42.
The central bank has sold a net total of $17.2 billion in foreign currency since the start of the year. The bank's forex reserves have fallen 4.2 percent since the end of 2012 as a result, but remain among the world's highest at $515.9 billion.
The bank said in a statement on Tuesday that it would adjust its daily interventions in future according to the volume of the finance ministry's operations to manage sovereign wealth funds.
The Finance Ministry plans to buy foreign exchange worth 10 to 30 billion roubles to top up its Reserve Fund and the National Welfare Fund this year, which are together worth 5.4 trillion roubles ($170 billion) and held at the central bank.
Previously, the funds were managed in off-market operations.
(Reporting by Maya Dyakina and Vladimir Abramov, editing by Jason Bush and Patrick Graham)