A powerful surge in Reliance Industries drove Indian equities sharply higher on Monday, lifting the Sensex by 1.66 per cent and pushing the Nifty 50 above the 23,400 mark as falling crude oil prices and renewed foreign buying improved market sentiment.

The 30 share BSE Sensex jumped 1,233.25 points to close at 75,692.78, while the NSE Nifty 50 gained 387.70 points to finish at 23,440.80. Both benchmark indices ended the session at their intraday highs, extending their winning streak to a third consecutive trading day.

Reliance Industries was the clear force behind the rally.

The company’s shares surged nearly 12 per cent, marking its third biggest single day gain in the past decade. The stock alone accounted for about 61 per cent of the Sensex’s gains and nearly half of the Nifty 50's advance, underlining the outsized influence of India’s most valuable listed company on the benchmark indices.

The rally came as investors responded positively to a combination of lower global oil prices, improving foreign portfolio investment flows and stronger risk appetite across Asian markets. Market breadth also remained positive, with advancing stocks comfortably outnumbering declining shares.

Broader markets joined the rally, although their gains were more modest than those of the headline indices. The Nifty MidCap 100 rose 1.19 per cent, while the Nifty SmallCap 100 gained 0.71 per cent.

Metal stocks were among the other major gainers. Tata Steel and JSW Steel posted strong advances as investors increased exposure to cyclical sectors. Oil marketing companies also moved higher after global crude prices dropped sharply on hopes of progress in negotiations between the United States and Iran.

Lower oil prices offer relief to India, one of the world's major crude importing economies. A sustained decline in energy costs could ease pressure on inflation, reduce the country's import bill and support corporate margins across several sectors.

Brent crude fell by about $10 to around $108 a barrel, providing a major boost to sentiment during the session.

Asian markets offered additional support. Equities in Japan, South Korea, China and Hong Kong largely closed higher as investors reacted to improving regional risk sentiment and lower energy prices. The positive global backdrop helped Indian markets maintain momentum throughout the day.

Foreign investors returned as buyers. Foreign portfolio investors recorded net equity purchases worth ₹3,115 crore, while domestic institutional investors were net sellers to the tune of ₹392 crore.

Despite the strong headline numbers, some market experts urged caution over the sustainability of the rally.

Nitin Bhasin, Head of Institutional Equities at Ambit, said the broader market narrative had not changed materially. He pointed to continuing geopolitical risks and concerns surrounding global artificial intelligence related trades, arguing that Monday's move was largely driven by Reliance's sharp recovery.

Because of the company's heavyweight position in India's benchmark indices, its near 12 per cent jump produced a disproportionate effect on both the Sensex and the Nifty, he said. Beyond that, he saw no immediate catalyst for a sustained market recovery.

Dhananjay Sinha, Co Head of Institutional Equities at Systematix, said investors appeared to be pricing in the prospect of lower oil prices and a gradual revival in foreign institutional flows. Both developments could support Indian equities if they continue.

He also said that a correction in artificial intelligence led global trades could improve India's relative appeal to overseas investors. But he cautioned that these expectations remained assumptions rather than confirmed trends.

The bond market reflected the improving sentiment. The benchmark 10 year government bond yield fell to 7.31 per cent, its lowest level in six months, supported by lower crude prices, continued foreign inflows and expectations of stable liquidity conditions.

The rupee, however, remained under pressure. The Indian currency weakened marginally by 5 paise to close at ₹94.90 against the US dollar.

For now, Reliance has given the market a powerful lift. Whether the broader rally can sustain itself will depend on crude prices, foreign fund flows, global risk sentiment and the emergence of stronger domestic triggers in the days ahead.