Forex market dealers said the main cause for appreciation was commercial banks selling American dollars to earn rupees. The Indian currency is quite short in supply following the Reserve Bank of India’s squeeze on liquidity. The banks need rupees to met their statutory needs. Even the inter-bank call money market rates about 10 days ago had surged to 80 per cent. The RBI is still keeping off the forex market and is likely to do so despite the rupee strengthening vis-à-vis the dollar because its priorities are to control inflation and stop credit expansion.