BENGALURU, Aug 26 (Reuters) - Indian shares rose marginally on Thursday, helped by a 1.5% jump in heavyweight Reliance Industries, while banks see-sawed between gains and losses ahead of the expiry of monthly derivatives contracts. By 0505 GMT, the blue-chip NSE Nifty 50 index and the benchmark S&P BSE Sensex were up 0.22% each at 16,671.1 and 56,069.3 respectively. The Nifty Bank index declined as much 0.5% before gaining 0.11%. Global ratings agency Moody’s has said Indian banks’ improved profitability and strong buffers will help them absorb rising risks from a resurgence in cases of COVID-19. Analysts like Sumit Pokharna, the vice president of research at Kotak Securities, however, also warn of bad loans. “Until concerns over non-performing assets reduce, the pressure on banks will remain.” Telecom major Bharti Airtel fell as much as 3.5% after it said it will consider various capital-raising options at a meeting this Sunday. The announcement comes as a surprise as there is no immediate need and it is unlikely Bharti would be looking to prepay spectrum liabilities to the government, Jefferies analysts said in a note. Swan Energy surged 17.8% after saying it planned to commission a unit in the western Indian state of Gujarat. Wockhardt Ltd jumped 6.5% as its unit was partnering with China’s Jiangxi Jemincare Group to supply a patented pneumonia antibiotic Nafithromycin in China, Hong Kong, Macau and Taiwan. Asian shares paused, while the U.S. S&P 500 closed at its 51st record high of the year, as investors focus on U.S. Fed Chair Jerome Powell’s Friday speech on tapering central bank’s bond-buying program. Meanwhile, a Reuters poll of analysts found Indian economic growth likely touched a record high in the quarter through June, reflecting a weak base and rebound in consumer spending. The GDP data is due to be released on Aug. 31. Reporting by Vishwadha Chander in Bengaluru; editing by Uttaresh.V Our Standards: The Thomson Reuters Trust Principles.