"Regulators will have to be careful about the tendency of some Indian corporations or entities without substantial foreign exchange earnings to leave foreign exchange borrowings un-hedged, so as to get 'cheap' foreign financing.
"Low un-hedged foreign interest rates can be deceptively enticing, leaving the borrower exposed to significantly higher repayments if the rupee depreciates unexpectedly," it said.
Several companies have been approaching the Reserve Bank to raise overseas debt as interest rates are low abroad.
The corporates raised USD 1.7 billion through external commercial borrowings (ECBs) in the April-September period of current fiscal, less than USD 8.4 billion in the corresponding period a year ago.
"India's external debt has remained within manageable limits as indicated by the external debt-GDP ratio... But the trends in size, source, maturity, and hedging of external debt bear careful monitoring," it said.
The total external debt amounted to USD 283.9 billion at end September, 2012.
The foreign exchange reserves at the end of January stood at USD 295.6 billion, up from USD 294.4 billion in March 2012.
Referring to the movement of rupee, the Survey said, the rupee has been more volatile.
The rupee touched an all-time low of 57.22 against the US dollar on June 27, 2012, thus depreciating by 10.6 per cent from 51.16 per dollar on March, 2012.
In the subsequent months of July to September 2012, the rupee appreciated, touching 51.62 per US dollar on October 5, 2012, and thereafter traded in the range of 53.02-54.78 during October 2012 to January 2013.
The rupee was trading at 53.90 a dollar in early trade.