At 0712 GMT, the rouble was 0.01 percent stronger against the dollar at 66.77. It had gained 0.01 percent to trade at 75.735 versus the euro.

The rouble typically receives support from month-end tax payments in the second half of the month as export-focused companies convert their foreign currency revenues to pay local liabilities.

But for now this support may be limited. Exporters are in no rush to sell foreign exchange before the Fed meeting and investors see risks of negative news for Russia, said Dmitry Polevoy, chief economist at the Russian Direct Investment Fund.

The Fed is widely expected to raise interest rates by 25 basis points on Wednesday on the second day of its Federal Open Market Committee meeting.

Brent crude oil, a global benchmark for Russia's main export, was down 1.43 percent at $58.76 a barrel.

Russian stock indexes were down, tracking a global fall in stocks as trading activity wound down towards the end of the year and Russia's long new year holidays.

"Taking into account sales on global markets, the Moscow exchange index today could try to renew its minimum for December, returning to the region of 2330-2350 points," Promsvyazbank's Mikhail Poddubsky said in a note.

The dollar-denominated RTS index was down 1.22 percent to 1099.870 points. The rouble-based MOEX Russian index  was 1.16 percent lower at 2331.80 points.