Mumbai, Aug. 19 -- The key equity indices traded with moderate gains in the mid-morning trade, buoyed by investor optimism surrounding potential GST reforms and positive developments in the Russia-Ukraine peace negotiations.

The Nifty traded above the 24,900 level. Auto shares extended gains for the two consecutive trading sessions.

At 11:30 ST, the barometer index, the S&P BSE Sensex, added 257.82 points or 0.31% to 81,519.55. The Nifty 50 index rose 65.95 points or 0.27% to 24,941.20.

The broader market outperformed the frontline indices. The S&P BSE Mid-Cap index added 0.42% and the S&P BSE Small-Cap index rose 0.62%.

The market breadth was strong. On the BSE, 2,434 shares rose and 1,382 shares fell. A total of 178 shares were unch...