The rupee depreciated 6 paise to 81.77 against the US dollar in early trade on Monday, tracking a lacklustre trend in domestic equity markets and a firm American currency overseas.

However, lower crude prices in the international market and fresh foreign fund inflows restricted the rupee's fall, forex dealers said.

At the interbank foreign exchange, the domestic unit opened weak at 81.81 against the dollar, then gained some ground to quote 81.77, registering a decline of 6 paise over its previous close.

In the previous session on Friday, the rupee weakened by just one paisa to end at 81.71 against the dollar.

The dollar index, which gauges the greenback's strength against a basket of six currencies, rose 0.41 per cent to 106.39.

Brent crude futures, the global oil benchmark, declined 2.58 per cent to USD 81.47 per barrel.

In the domestic equity market, the 30-share BSE Sensex was trading 27.97 points or 0.04 per cent lower at 62,265.67. Similarly, the broader NSE Nifty fell 12.45 points or 0.07 per cent to 18,500.30.

Foreign Institutional Investors (FIIs) were net buyers in the capital markets on Friday as they bought shares worth Rs 369.08 crore, according to exchange data.

Foreign portfolio investors have rediscovered their liking for Indian equities, making a net investment of Rs 31,630 crore in November in hopes of an end to the aggressive rate hikes and positivity about overall macroeconomic trends.