Dealers attributed the rupee's fall to increased demand for the US currency from importers and banks and a lower opening in the domestic equity market.
On Friday, the rupee had lost 12 paise to close lower at 64.70 a dollar due to renewed demand for the US currency.
Foreign investors pulled out Rs 416.28 crore from equity markets on Friday, as per provisional data.
Standard & Poor's on Friday kept its sovereign rating for India unchanged at 'BBB-minus' with 'stable' outlook saying vulnerabilities stemming from low per capita income and high government debt balance strong GDP growth.