Mumbai: Indian Rupee gained 33 paise to 81.77 against the US dollar in early trade on Monday amidst sustained foreign fund inflows and bullish momentum in domestic equities. Earlier on Friday, the rupee closed at 82.10 against the US dollar. At the interbank foreign exchange, the domestic unit opened weak at 82.01 against the dollar. The currency touched rose to 81.77, registering 33 paise gain. The rupee was likely to trade between 81..90 to 82.29 during the day. Meanwhile, the dollar index, which gauges the greenback’s strength against a basket of six currencies, rose 0.05 per cent to 102.96. Brent crude futures, the global oil benchmark traded 0.07 per cent to USD 75.46 per barrel.