At 11:31 a.m. (0601 GMT), the partially convertible rupee was at 48.72/73 to a dollar, after dipping to 48.85 -- a level last seen on Sept. 4, 2009.
The unit had closed 0.6 percent weaker at 48.325/335 on Wednesday.
Calls for intervention by the Reserve Bank of India in the foreign exchange market have increased in the past few weeks as the rupee has been under almost continuous selling pressure on deepening concerns over global economic growth.
"Hope is that RBI will intervene sooner than later if the weakness is expected to continue. The rupee has already lost more than 10 percent from its peak this year," said a senior treasury official at a private-sector bank. The unit has lost 10.21 percent at this session's low from its strongest point this year of 43.8550 per dollar on July 27. Two traders said the RBI may have sold dollars through state-owned banks, while two others said rupee may have found support due to dollar selling by a large British bank.
The dollar climbed to a seven-month high against major currencies on Thursday after the Federal Reserve said there were "significant downside risks" to the economy, but it stopped short of bold monetary easing.
The index of the dollar against six major currencies was up 0.76 percent at 77.928 points. It was at 77.248 points when the rupee closed on Wednesday.
Foreign exchange authorities in South Korea, Indonesia and the Philippines have bought their respective currencies in the past few days to limit their falls, according to traders.
Traders believe the rupee may move past the 49 mark if there is strong month-end dollar demand from domestic oil refiners, and if active support from the central bank for the local unit is absent.
Oil is India's biggest import item and local oil refiners are the largest purchasers of dollars in the domestic currency market.
Indian shares fell 2 percent after the Fed's warning sent markets across the world sliding.
The one-month onshore forward premium was at 18.75 points from 17.50 on Wednesday, the three-month was at 58 points from 50.75 and the one-year was at 124 points from 114.75.
The one-month offshore non-deliverable forward contracts were quoted at 49.04, weaker than the onshore spot rate.
In the currency futures market, the most traded near-month dollar-rupee contracts on the National Stock Exchange, the MCX-SX and the United Stock Exchange were all at 48.7675. The total volume was $2.89 billion.