Benchmarks opened on a positive note Monday as sentiments turned bullish in global markets post US GDP data. All the sectoral indices were in the green with metals, realty and auto in the lead.

A slightly better than expected US GDP data and some inspiring talk by Ben Bernanke lifted the sagging spirits on Wall Street and elsewhere. Not surprisingly, Asian markets are all up smartly. News that Bank of Japan is holding an emergency meeting to check unbridled gains in the yen has also buoyed sentiment.

Given the positive backdrop, we are set for a gap-up opening. Some shorts may be covered as well. The big question is whether one should buy into this rally or sell? We would urge some caution as the global situation, especially in the US, looks precarious. At best what we will see is a relief rally. Things may soon turn choppy and range-bound.

A lot of uncertainty still prevails in global markets. Dont get too inspired to jump the gun and take big directional calls. Keep reviewing your strategy each day as volatility is here to stay. Key events in the near term include Q1 GDP data (on Tuesday), auto sales, IIP, inflation and the RBI meeting, said IIFL report.

At 9:40 am, Bombay Stock Exchanges Sensex was at 18128.52, up 130.11 points or 0.72 per cent. The index touched a high of 18216.50 and low of 18063.48 in trade so far.

National Stock Exchanges Nifty was at 5443.60, up 34.90 points or 0.65 per cent. The broader index touched intraday high of 5469 and low of 5408.90.

BSE Midcap Index was up 1.06 per cent and BSE Smallcap Index moved 1.23 per cent higher.

Amongst the sectoral indices, BSE Metal Index advanced 1.74 per cent, BSE Realty Index moved 1.35 per cent higher and BSE Auto Index gained 1.08 per cent.

Tata Steel (2.73%), Hindalco Industries (2.54%), ONGC (2.20%), ICICI Bank (1.79%) and Jindal Steel (1.65%) led the Sensex gainers.

TCS (-0.79%), Infosys Technologies (-0.51%), HDFC Bank (-0.34%) and ITC (-0.19%) were the only losers.

Market breadth was positive on the BSE with 1787 advances against 438 declines.

Meanwhile, the Asian markets were in the positive terrain. Nikkei 225 was up 2.27 per cent, Shanghai Composite moved 1.45 per cent higher and Seoul Composite gained 1.52 per cent.