US dollar firms up further against rupee

The US dollar firmed up further against the rupee at 66.66/67 per dollar but the pound sterling finished sharply lower at Rs 93.58/60 per pound at the close of the Interbank Foreign Exchange market today.
Following are the Interbank Forex and RBI rates:
(In Rs Per Unit)
Unit Interbank RBI Reference US Dollar 66.66/67 US Dollar Rs.66.5807 Pound Sterling 93.58/60 Euro Rs.75.6290 Euro 75.55/57
Japanese Yen (100) 60.