The Sensex resumed higher at 20,643.85 and firmed up to 20,694.42 on initial buying. However, it declined afterwards to 20,629.56 before quoting at 20,652.37 at 1030 hrs, a gain of 18.16 points or 0.09 per cent, from its last close.
The NSE 50-share Nifty also moved up by 6.95 points, or 0.11 per cent, to 6,134.05 at 1030 hrs.
However, SSTL fell by 1.37 per cent, Tata Steel (1.35 per cent), HDFC (1.11 per cent), Tata Power (1.07 per cent) and Maruti (0.66 per cent).
Foreign institutional investors (FIIs) bought shares worth a net Rs 292.23 crore yesterday, says provisional data from the stock exchanges.
US stocks settled mostly higher yesterday with the NASDAQ Composite recording its eighth consecutive session of gains, the longest since July 2013.
However, most Asian stocks fell in early trade today. Key benchmark indices in Hong Kong, Japan, South Korea and Taiwan fell in the range of 0.02 per cent and 0.68 per cent while indices in China and Singapore were up between 0.37 per cent and 0.63 per cent.