KOLKATA: US private equity firm Brookfield Asset Management has emerged a serious bidder to buy Reliance CommunicationsBSE -3.15 %' stake in its tower unit, three people aware of the matter told ET. The talks with Brookfield follow Sanjiv Ahuja-led Tillman Global Holdings' failure to find a suitable financier for the Anil Ambani-led telco's tower assets. RCom's plans to sell its RelianceInfratel towers business has been hanging fire ever since TPG Capital valued it well below the Rs 21,500 crore initially discussed, which in turn prompted Tillman Global to scout for other potential financiers. Last December, RCom announced that the TPG-Tillman combine had made a non-binding pact to buy its tower assets. RCom, the country's fourth-largest telco, has been seeking to pare its mammoth debt, pegged at Rs 42,000 crore.