The US Federal Reserve interest rate decision on Thursday will be a major event that would be keenly tracked by markets globally.
The BSE Sensex settled at 40,445.15, down 334.44 points or 0.82 per cent.
The BSE gauge Sensex moved 103.13 points higher to trade at 40,882.72 in opening deals.
At the closing bell, the 30-share BSE Sensex was lower by 70.70 points or 0.17 per cent at 40,779.59.
BSE Sensex was trading 100.56 points, lower at 40,749.73 at 1149 hours.
The 30-share BSE Sensex was trading higher by 84.17 points at 40,934.46 in n opening deals.
Sectorally, BSE metal index rose the most by 1.66 per cent, followed by bankex and IT indices.
The 30-share BSE Sensex was down 119.42 points or 0.29 per cent to 40,556.03 in early deals.
The 30-share BSE gauge settled at 40,675.45, down 0.31 per cent or 126.72 points.
The fresh trade war tensions along with unabated foreign fund outflows weighed heavily on the market sentiments, traders said.