After trading on Thursday near seven-month highs, the rouble had begun to weaken before the central bank announcement, pressured by lower oil prices and a stronger dollar.

A dealer with a Western bank in Russia said investors had decided to take profits ahead of the weekend and as the rouble was already overbought.

The Russian currency had risen earlier in the week, buoyed by the US Federal Reserve policy announcements and higher oil prices.

At 1145 GMT, the rouble was 0.73 percent weaker against the dollar at 64.34 and had lost 0.08 percent to trade at 72.69 versus the euro.

Brent crude oil, a global benchmark for Russia's main export, was down 1.09 percent at $67.12 a barrel.

There have been suggestions from the central bank that it could cut the rate later this year because the pace of inflation is expected to slow. But the rouble remained neutral both to the decision to keep the key rate on hold and to the central bank statement, said Dmitry Polevoy, chief economist at Russian Direct Investment Fund.

"The policy-easing prospects will keep OFZ (Russian government bonds) and the rouble assets appealing, potentially driving further portfolio capital inflows," he said.

Russian stock indexes were down.