Mumbai, Jan 29 (IANS): Nifty ended the first day of the week with its biggest single-day gain since December 4 with heavyweight Reliance Industries contributing the most to the gains, Deepak Jasani, Head Retail Research at HDFC Securities, said on Monday.

At close on Monday, Nifty was up 385 points or 1.8 per cent at 21,737.60, while Sensex closed the day 1,240.90 points or 1.76 per cent higher at 71,941.57.

Cash market volumes on the NSE were high at Rs 1.26 lakh crore. Broad market indices rose less than the Nifty even as the advance-decline ratio remained up at 1.39:1, Jasani said.

The buildup ahead of the vote on account seems to have started. This upmove can be used for selectively reducing weight in individual stocks that have run up too fast, he said.

Vaibhav Vidwani, Research Analyst at Bonanza Portfolio, said Nifty Oil and Gas and Nifty Energy were the sectors which outperform on Monday, up by 5.18 per cent and 5.17 per cent, respectively.

Excitement among the investors ahead of the interim budget, which is likely to include major allocations to infrastructure and energy, is partly responsible for the Nifty 50's recent rally, he said.

Government expenditure in these sectors usually indicates strong growth potential, which draws interest from the investors, so this confidence is not unwarranted. Further upswings are also observed in certain industries, such defence and railways, perhaps as a result of anticipations around targeted fiscal assistance, Vidwani said.

ONGC, Reliance Industries, Adani Enterprises, Coal India, and Adani Ports were the top gainers on the Nifty on Monday, while Cipla, ITC, LTIMindtree, Bajaj Auto, and Infosys were the top losers.