Indian equity markets fell sharply in early Monday trade after US-Iran negotiations broke down in Pakistan, stoking investor anxiety over regional stability. The two sides failed to reach an agreement following a marathon 21-hour session, casting doubt over a fragile two-week ceasefire, with each blaming the other for the collapse. All 30 companies on the Sensex (India's benchmark stock index) were trading lower, with Titan, Sun Pharma, and Bharti Airtel among the hardest hit.