Continuing its rising spree, the rupee appreciated another 50 paise to breach the 70 per dollar-mark in opening trade Wednesday on a persistent drop in crude prices amid fresh foreign fund inflows and sustained selling of the American currency by exporters and banks.
Besides, the dollar's weakness against some currencies overseas ahead of US Federal Reserve's policy meet outcome later in the day also supported the rupee.
The domestic unit opened with strength at Rs 70.05 at the Interbank Foreign Exchange and advanced further to 69.87 against the US dollar.
Brent crude, an international benchmark, dropped 4.2 per cent lower to USD 57.07 per barrel Tuesday, a 14-month low.
The rupee Tuesday rallied by a whopping 112 paise, its best single-day gains in over five years, to settle at 70.44 against the US dollar as softening crude oil prices eased concerns over India's current account deficit expansion.
Foreign institutional investors (FIIs) bought shares worth Rs 144.76 crore Tuesday, as per provisional data.
Meanwhile, the benchmark BSE Sensex rose 112.32 points, or 0.31 per cent, to 36,459.09 in opening trade.