The Indian rupee weakened slightly against the US dollar on Monday, slipping by 1 paisa to 90.67 in early trade. Forex traders blamed foreign institutional investors (FII) selling, a stronger US dollar, and a small rise in global crude oil prices. India's forex reserves also fell sharply, adding pressure on the rupee. The rupee initially opened stronger at 90.63 before dropping to 90.67. On Friday, it settled 5 paise lower at 90.66. Anil Kumar Bhansali, Executive Director at Finrex Treasury Advisors LLP, said, "The rupee opened slightly stronger from Friday close and should remain in a small range on a day when cash demand will be lower due to U.S. Presidential Day holiday." He added that markets will closely watch India's trade balance data, expected to be released Monday. The dollar index, which tracks the dollar against six currencies, gained 0.02% to 96.93. Brent crude oil prices also inched up by 0.04% to $67.78 per barrel. On the equity front, Sensex fell 71.53 points to 82,555.23, and Nifty dropped 11.95 points to 25,459.15 during early trading. On Friday, FIIs sold equities worth ₹7,395.41 crore. Reserve Bank data showed India's forex reserves declined by $6.711 billion to $717.064 billion in the week ending February 6. This came after a record jump of $14.361 billion to $723.774 billion the previous week.