The rupee weakened to 64.73 due to fresh demand for the American currency from banks and importers.
Moreover, a weak domestic equity market put the rupee on backfoot, forex dealers said.
The domestic unit opened weak by 10 paise at 64.60 at the Interbank Foreign Exchange market today. It hovered in a range of 64.73 and 64.53 before quoting at 64.69, down 19 paise at 4.10 pm local time.
Yesterday, the rupee had recovered some of the lost ground and ended higher 6 paise at 64.50 against the US dollar amid mild selling of the American currency by exporters.
Meanwhile, the 30-share BSE index Sensex ended lower by 144.87 points or 0.49 per cent at 29,643.48
The yen hit five-month highs against the dollar, euro and sterling on Wednesday, as simmering geopolitical tensions checked risk appetite and put the safe-haven Japanese currency in favour.
Investors' flight-to-safety underpinned traditional safe-havens like the yen, U.S. Treasuries and gold, amid fresh worries over France's presidential election, and possible U.S. military action against Syria and North Korea.
The dollar fell on Tuesday and added to those losses on Wednesday, edging down 0.1 per cent against a basket of major currencies to 100.62.