The Indian rupee may drop past 88 to the U.S. dollar to an all-time low on Tuesday after U.S. President Donald Trump threatened steeper tariffs on Indian goods, worsening fragile sentiment and stoking concerns of more foreign outflows. The 1-month non-deliverable forward indicated the rupee will open in the 88.00 to 88.04 range versus the U.S. dollar, down from 87.6550 on Monday. The rupee’s previous record low was 87.95, touched in February. Trump again threatened to substantially raise tariffs on Indian goods, citing India's continued purchases and resale of Russian oil. India’s foreign ministry responded, saying it will take all...