Mumbai, Sep 20 (IANS): The Indian rupee ended almost flat against the US dollar on Tuesday with just 2 paise gain, at 79.75.

Dealers said that the marginal rise was witnessed due to gains in domestic equities and traders remained on sidelines ahead of the US Fed announcement.

At the interbank foreign exchange market, rupee ended at 79.75, as against 79.77 on the previous trading session.

"In the last two days, the rupee consolidated in the range of 79.80 to 79.55. RBI's intervention and dollar inflows remain the main driver of the rupee's outperformance in the last few days," Dilip Parmar, Research Analyst, HDFC Securities, said.

"We see a mixed bag with overall small moves in the rupee ahead of the FOMC rate decision," he added.

"Spot USDINR is expected to trade within the range of 79.40 to 79.90," he said.

Dollar index, which gauges the the strength of greenback against the basket of six major currencies, was at 109.520.

Brent crude oil prices were at $92.15 a barrel by the closing of Indian market hours.

Meanwhile, benchmark indices ended higher on Tuesday with Sensex rising over 550 points and Nifty over 190 points due to support from pharma, auto, and financial stocks, dealers said.

At close, Sensex ended 578.51 points, or 0.98 per cent, up at 59,719.74, and Nifty ended 194 points, or 1.10 per cent, up at 17,816.25.