Indian equity benchmarks posted modest gains on Thursday, extending their winning streak for a fourth straight session, buoyed by optimism surrounding India-U.S. trade talks, expectations of GST relief measures, and global cues hinting at potential rate cuts by the U.S. Federal Reserve. The Sensex closed above Rs. 81,500, while the Nifty 50 reclaimed the psychologically important Rs. 25,000 mark. Gains were led by banking, energy, and PSU stocks, although profit-booking weighed on IT and auto counters.