The BSE benchmark Sensex fell by over 126 points in opening trade today. This follows funds and retail investors selling ahead of the Reserve Bank of India's monetary policy review meeting later in the day. The 30-share Bombay Stock Exchange barometer, which lost 176 points in the previous session, fell further to slightly over 18,000 points within the first few minutes of trade. Similarly, the wide-based National Stock Exchange Nifty index declined by 41.10 points, to 5,406.