Mumbai:  The Bombay Stock Exchange benchmark Sensex on Tuesday spurted over 421 points - biggest gain in two weeks - on fresh inflows amid some positives, including RBI's plan to reverse tight monetary policy stance, and a firm global equities.

Sensex, which had gained 63 points on Monday, surged another 421.44 points, or 2.72 percent to 15,939.36 as two heavyweights Reliance Industries and Infosys gained over two percent each. While RIL shot up 2.37 percent, Infosys gained 2.13 percent.

After losing 25 percent last year due to high inflation, soaring interest rates and the weakening rupee, Indian markets have commenced the New Year on a positive note amid the government's allowing foreign individuals to invest in stocks, and RBI saying that it may reverse tight money policy stance.

The NSE 50-issue index Nifty gained 128.55, or 2.77 percent to 4,765.30.

Metals, capital goods and banks led the gains.

A firm trend in Asian markets and higher opening in Europe further supported the uptrend on growth in the region's manufacturing sector.

In the broader market, Network18 Media and TV18 Broadcast jumped 17.77 percent and 18.25 percent on reports that RIL plans to invest more than Rs 1,500 crore in TV18.

The metals sector index gained 5.05 per cent at 9,825.01, followed by capital goods - 4 percent at 8,458.64. Banking index rose 4.35 percent to 9,576.99 and realty index by 4.28 percent to 1,428.90.