The Indian rupee slumped to a three-week low in opening trades on Tuesday as investors were cautious ahead of the implementation of the August 27 tariff deadline, with an additional 25% duty on Indian goods set to take effect this week. Rupee opened at Rs 87.74 per dollar but managed to recover to a high of 87.69 so far during the day. Yesterday, rupee pared initial gains to settle 4 paise lower at 87.56 against the US dollar. Indian shares are likely to open on a weak note on Tuesday. Benchmark indexes Sensex and Nifty rose around 0.4 percent each on Monday as IT stocks surged on Fed rate cut hopes. Asian markets traded lower this morning while the dollar and U.S. Treasuries slid after U.S. President Donald Trump said on social media he was removing Lisa Cook from her position on the Fed's board of directors, the latest in a series of attacks on the central bank's independence.