The rupee appreciated 4 paise to 77.66 against the US dollar in the opening trade on Monday as a positive trend in domestic equities and weak American currency overseas supported the local unit.

However, unabated foreign fund outflows and surging crude prices in the international markets restricted the rupee's gain, forex dealers said.

At the interbank foreign exchange, the rupee opened slightly strong at 77.69 against the American dollar, then gained some more ground to quote 77.66, registering a rise of 4 paise over the last close. It was moving in a narrow range of 77.66 to 77.69 in early deals.

In the previous session, the rupee had settled at a record low of 77.70 against the American currency.

The dollar index, which gauges the greenback's strength against a basket of six currencies, was trading 0.42 per cent lower at 102.71.

On the domestic equity market front, the 30-share Sensex was trading 166.35 points or 0.31 per cent higher at 54,492.74, while the broader NSE Nifty gained 30.70 points or 0.19 per cent to 16,296.85.

Global oil benchmark Brent crude futures surged 0.52 per cent to USD 113.14 per barrel.

The government on Saturday announced a record Rs 8 per litre cut in excise duty on petrol and Rs 6 per litre reduction on diesel.

Foreign institutional investors remained net sellers in the capital market on Friday as they offloaded shares worth Rs 1,265.41 crore, as per stock exchange data.

The exodus of foreign money from the Indian equity markets continues unabated, with FPIs pulling out over Rs 35,000 crore so far this month on concerns over the prospects of a more aggressive rate hike by the US Fed and appreciation of the dollar.

With this, net outflow by Foreign Portfolio Investors (FPIs) from equities reached Rs 1.63 lakh crore so far in 2022.