MOSCOW, Sept 21 (Reuters) - The Russian rouble firmed versus the dollar on Tuesday, recovering from a three-week low hit in the previous session, as oil prices pared some losses and investors looked ahead to a U.S. Federal Reserve meeting. At 0714 GMT, the rouble was 0.2% stronger against the dollar at 73.25 and had gained 0.2% to trade at 85.94 versus the euro. “We do not expect strong volatility on the foreign exchange market,” said Promsvyazbank analysts in a note, with the rouble expected to partially recoup some of Monday’s losses. Investors are focused on the Federal Reserve’s Sept. 21-22 meeting, bracing for it to take another step towards tapering stimulus. “Investors will be cautious ahead of the Fed meet, fearing that the regulator may signal the beginning of a tighter policy,” wrote BCS Global Markets analysts. Brent crude oil, a global benchmark for Russia’s main export, was up 1% at $74.65 a barrel, pulling Russian stock indexes, which had sunk to near three-week lows on Monday, higher. The dollar-denominated RTS index was up 0.8% to 1,713.6 points. The rouble-based MOEX Russian index was 0.4% higher at 3,983.8 points. Oil major Rosneft’s shares jumped 2.4% after a newspaper report said the Russian government could allow the company to export 10 billion cubic metres of natural gas to Europe a year on a trial basis.Shares in Russian gas giant Gazprom also ticked up 1.3% amid a gas price surge in Europe that threatens to push up winter fuel bills, hurt consumption and exacerbate a near-term spike in inflation. For Russian equities guide see For Russian treasury bonds see