The rupee declined by 34 paise to close at one-week low of 66.48 against the US dollar on persistent month-end demand for the American currency from importers despite a lower greenback in the overseas market.
Besides, fresh fall in equity market affected the value of the rupee against the US dollar.
The domestic currency resumed lower at 66.25 against last Friday's closing level of 66.14 at the Interbank Foreign Exchange (Forex) market and dropped further to 66.49 before ending at one-week low of 66.48, showing a loss of 34 paise or 0.51 per cent.
The rupee had last closed at 66.65 on August 24, 2015. It has lost 44 paise, or 0.67 per cent, in last two days.
It moved in a range of 66.49 and 66.20 during the day.
Oil prices fell in Asia today, coming under pressure as dealers took profits from huge gains in the previous session and tried to gauge the outlook for the US economy and its taste for crude.
US benchmark West Texas Intermediate for October delivery eased 79 cents to USD 44.43 while Brent crude for October fell USD 1.00 to USD 49.05 in late-morning trade.
Meanwhile, the benchmark BSE Sensex ended lower by 109.29 points, or 0.41 per cent, to settle at 26,283.09.
