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.

President Donald Trump said he would be “substantially raising” the tariff on Indian exports to the US over the Asian nation’s purchases of Russian oil, a move New Delhi slammed as unjustified in an escalating fight between the two major economies.

U.S. President Donald Trump said on Monday he will substantially raise tariffs on India over its purchases of Russian oil.