Buy or sell stocks, Aug. 20 -- The key benchmark indices of the Indian stock market extended gains for the fourth session amid strong global cues. Investor sentiment remained buoyed by reports of a streamlined Goods and Services Tax (GST) structure, expected to boost spending and fuel consumption. The Nifty 50 index started the session flat; however, it gained momentum as the session progressed to form an intraday high of 25,012 in the mid-session. The 50-stock index thereafter consolidated in a range to close just below the 25,000 levels. At close, the Sensex was up 370 points or 0.46% at 81,644, and the Nifty was up 103 points or 0.42% at 24,980.

Among sectors, except pharma, all other sectoral indices ended in the green, with telecom,...