Equity benchmark Sensex tumbled over 540 points in opening trade on Thursday, tracking losses in banking and financial stocks amid a weak trend in global equity markets.

The 30-share BSE benchmark was trading 546.31 points lower at 57,138.51. Similarly, the broader NSE Nifty declined 154.5 points to 17,091.15.

From the 30-share pack, Kotak Mahindra Bank, Titan, ICICI Bank, HDFC Bank, HDFC, IndusInd Bank, Bajaj Finance and Axis Bank were the major drags in early trade.

In contrast, Dr Reddy's Laboratories, ITC, TCS, and Tata Steel were among the gainers.

"The market now lacks direction and is moving up or down on a daily basis responding to news regarding crude price, FPI flows and speculation on what the Fed might do in the coming policy meets," said VK Vijayakumar, Chief Investment Strategist at Geojit Financial Services.

In the previous trade, the BSE barometer declined 304.48 points or 0.53 per cent to settle at 57,684.82. The Nifty dipped 69.85 points or 0.4 per cent to finish at 17,245.65.

Equity exchanges in Tokyo, Seoul and Shanghai were quoting lower in mid-session deals, while Hong Kong traded marginally higher.

Stock exchanges in the US ended on a negative note in the overnight session.

Meanwhile, international oil benchmark Brent crude surged to USD 120.88 per barrel.

Foreign institutional investors (FIIs) were net buyers as they bought shares worth Rs 481.33 crore on Wednesday, according to stock exchange data.