The local unit resumed lower at 54.70 a dollar at the Interbank Foreign Exchange (Forex) Market and plunged to a new all-time low of 54.99 against the US dollar at 1640 hours.
Forex dealers said fresh dollar demand from banks and particularly, month-end demand from oil importers despite weakness of the dollar in the overseas market pulled down the rupee.
Meanwhile, the BSE benchmark Sensex erased most of the day's gains and settled 30.51 points higher at 16,183.26.